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langbeinites

{{short description|Class of chemical compounds}}

Langbeinites are a family of crystalline substances based on the structure of langbeinite with general formula {{chem2|M2M'2(SO4)3}}, where M is a large univalent cation (such as potassium, rubidium, caesium, or ammonium), and M' is a small divalent cation (for example, magnesium, calcium, manganese, iron, cobalt, nickel, copper, zinc or cadmium). The sulfate group, {{chem2|SO4(2-)}}, can be substituted by other tetrahedral anions with a double negative charge such as tetrafluoroberyllate ({{chem2|BeF4(2-)}}), selenate ({{chem2|SeO4(2-)}}), chromate ({{chem2|CrO4(2-)}}), molybdate ({{chem2|MoO4(2-)}}), or tungstates. Although monofluorophosphates are predicted, they have not been described. By redistributing charges other anions with the same shape such as phosphate also form langbeinite structures. In these the M' atom must have a greater charge to balance the extra three negative charges.

At higher temperatures the crystal structure is cubic P213. However, the crystal structure may change to lower symmetries at lower temperatures, for example, P21, P1, or P212121. Usually this temperature is well below room temperature, but in a few cases the substance must be heated to acquire the cubic structure.

Crystal structure

The crystal structures of langbeinites consist of a network of oxygen vertex-connected tetrahedral polyanions (such as sulfate) and distorted metal ion-oxygen octahedra. The unit cell contains four formula units. In the cubic form the tetrahedral anions are slightly rotated from the main crystal axes. When cooled, this rotation disappears and the tetrahedra align, resulting in lower energy as well as lower crystal symmetry.

Examples

Sulfates include dithallium dicadmium sulfate,{{cite journal |last=Guelylah |first=A. |author2=G. Madariaga |author3=W. Morgenroth |author4=M. I. Aroyo |author5=T. Breczewski |author6=E. H. Bocanegra |year=2000 |title=X-ray structure determination of the monoclinic (121 K) and orthorhombic (85 K) phases of langbeinite-type dithallium dicadmium sulfate |journal=Acta Crystallographica Section B |volume=56 |issue=6 |pages=921–935 |doi=10.1107/S0108768100009514 |pmid=11099956|bibcode=2000AcCrB..56..921G }} dirubidium dicadmium sulfate,{{cite journal |last=Guelylah |first=Abderrahim |author2=Gotzon Madariaga |year=2003 |title=Dirubidium dicadmium sulfate at 293 K|journal=Acta Crystallographica Section C |volume=59 |issue=5 |pages=i32–i34 |doi=10.1107/S0108270103007479 |pmid=12743381|bibcode=2003AcCrC..59I..32G }} dipotassium dicadmium sulfate,{{cite journal |last=Guelylah |first=A. |author2=M. I. Aroyo |author3=J. M. Pérez-Mato |year=1996 |title=Microscopic distortion and order parameter in langbeinite K2Cd2(SO4)3 |journal=Phase Transitions |volume=59 |issue=1–3 |pages=155–179 |doi=10.1080/01411599608220042|bibcode=1996PhaTr..59..155G }} dithallium manganese sulfate,{{cite journal |last=Zemann |first=Anna |author2=J. Zemann |year=1957 |title=Die Kristallstruktur von Langbeinit, K2Mg2(SO4)3 |journal=Acta Crystallographica |volume=10 |issue=6 |pages=409–413 |doi=10.1107/S0365110X57001346|doi-access=free |bibcode=1957AcCry..10..409Z }} and dirubidium dicalcium trisulfate.{{cite journal |last=Boujelben |first=Mohamed |author2=Mohamed Toumi |author3=Tahar Mhiri |year=2007 |title=Langbeinite-type Rb2Ca2(SO4)3 |journal=Acta Crystallographica Section E |volume=63 |issue=7 |pages=i157 |doi=10.1107/S1600536807027043|bibcode=2007AcCrE..63I.157B }}

Selenates include diammonium dimanganese selenate. A diammonium dicadmium selenate langbeinite could not be crystallised from water, but a trihydrate exists.{{cite journal |last1=Martínez |first1=M. L. |last2=Rodriguez |first2=A. |last3=Mestres |first3=L. |last4=Solans |first4=X. |last5=Bocanegra |first5=E. H. |title=Synthesis, crystal structure, and thermal studies of (NH4)2Cd2(SeO4)3·3H2O |journal=Journal of Solid State Chemistry |date=November 1990 |volume=89 |issue=1 |pages=88–93 |doi=10.1016/0022-4596(90)90297-B |bibcode=1990JSSCh..89...88M }}

Chromate based langbeinites include dicaesium dimanganese chromate.

Molybdates include {{chem2|Rb2Co2(MoO4)3}}. Potassium members are absent, as are zinc and copper containing solids, which all crystallize in different forms. Manganese, magnesium, cadmium and some nickel double molybdates exist as langbeinites.{{cite journal |last=Солодовникова |first=С. Ф. |author2=Солодовникова, В. А. |year=1997 |title=Новый тип строения в морфотропном ряду A+2M+2(MoO4)3: кристаллическая структура Rb2Cu2(MoO4)3 |journal=ЖУРНАЛ структур. химии |volume=38 |issue=5 |pages=914–921 |language=Russian |url=http://jsc.niic.nsc.ru/JSC/jsc_rus/1997-t38/n5/V38_N5_12.pdf}}

Double tungstates of the form {{chem2|A2B2(WO4)3}} are predicted to exist in the langbeinite form.

An examples with tetrafluroberyllate is dipotassium dimanganese tetrafluoroberyllate ({{chem2|K2Mn2(BeF4)3}}).{{cite journal |last=Guelylah |first=A. |author2=T. Breczewski |author3=G. Madariaga |year=1996 |title=A New Langbeinite: Dipotassium Dimanganese Tetrafluoroberyllate |journal=Acta Crystallographica Section C |volume=52 |issue=12 |pages=2951–2954 |doi=10.1107/S0108270196008827|bibcode=1996AcCrC..52.2951G }} Other tetrafluoroberyllates may include: {{chem2|Rb2Mg2(BeF4)3}}; {{chem2|Tl2Mg2(BeF4)3}}; {{chem2|Rb2Mn2(BeF4)3}}; {{chem2|Tl2Mn2(BeF4)3}}; {{chem2|Rb2Ni2(BeF4)3}}; {{chem2|Tl2Ni2(BeF4)3}}; {{chem2|Rb2Zn2(BeF4)3}}; {{chem2|Tl2Zn2(BeF4)3}}; {{chem2|Cs2Ca2(BeF4)3}}; {{chem2|Rb2Ca2(BeF4)3}}; {{chem2|RbCsMnCd(BeF4)3}}; {{chem2|Cs2MnCd(BeF4)3}}; {{chem2|RbCsCd2(BeF4)3}}; {{chem2|Cs2Cd2(BeF4)3}}; {{chem2|Tl2Cd2(BeF4)3}}; {{chem2|(NH4)2Cd2(BeF4)3}}; {{chem2|KRbMnCd(BeF4)3}}; {{chem2|K2MnCd(BeF4)3}}; {{chem2|Rb2MnCd(BeF4)3}}; {{chem2|Rb2Cd2(BeF4)3}}; {{chem2|RbCsCo2(BeF4)3}}; {{chem2|(NH4)2Co2(BeF4)3}}; {{chem2|K2Co2(BeF4)3}}; {{chem2|Rb2Co2(BeF4)3}}; {{chem2|Tl2Co2(BeF4)3}}; {{chem2|RbCsMn2(BeF4)3}}; {{chem2|Cs2Mn2(BeF4)3}}; {{chem2|RbCsZn2(BeF4)3}}; {{chem2|(NH4)2Mg2(BeF4)3}}; {{chem2|(NH4)2Mn2(BeF4)3}}; {{chem2|(NH4)2Ni2(BeF4)3}}; {{chem2|(NH4)2Zn2(BeF4)3}};{{chem2|KRbMg2(BeF4)3}}; {{chem2|K2Mg2(BeF4)3}}; {{chem2|KRbMn2(BeF4)3}}; {{chem2|K2Ni2(BeF4)3}};

{{chem2|K2Zn2(BeF4)3}}.{{Cite book |last=Pies |first=W. |author2=A. Weiss |year=1973 |volume=7a |pages=91–103 |doi=10.1007/10201462_9 |chapter=A458, I.1.3 Complex fluorides and fluorine double salts |title=Key Elements: F, Cl, Br, I |series=Landolt-Börnstein - Group III Condensed Matter |isbn=978-3-540-06166-3}}

The phosphate containing langbeinites were found in 1972 with the discovery of {{chem2|KTi2(PO4)3}}, and since then a few more phosphates that also contain titanium have been found such as {{chem2|Na2FeTi(PO4)3}} and {{chem2|Na2CrTi(PO4)3}}. By substituting metals in {{chem2|A2MTi(PO4)3}}, A from (K, Rb, Cs), and M from (Cr, Fe, V), other langbeinites are made. The NASICON-type structure competes for these kinds of phosphates, so not all possibilities are langbeinites.

Other phosphate based substances include {{chem2|K2YTi(PO4)3}}, {{chem2|K2ErTi(PO4)3}}, {{chem2|K2YbTi(PO4)3}}, {{chem2|K2CrTi(PO4)3}},{{cite journal |last=Norberg |first=Stefan T. |year=2002 |title=New phosphate langbeinites, K2MTi(PO4)3 (M = Er, Yb or Y), and an alternative description of the langbeinite framework |journal=Acta Crystallographica B |volume=58 |issue=5 |pages=743–749 |pmid=12324686 |doi=10.1107/S0108768102013782 |pmc=2391006|bibcode=2002AcCrB..58..743N }} {{chem2|K2AlSn(PO4)3}},{{cite journal |last=Li |first=Hai-Yan |author2=Dan Zhao |year=2011 |title=A new langbeinite-type phosphate: K2AlSn(PO4)3 |journal=Acta Crystallographica Section E |volume=67 |issue=10 |pages=i56 |doi=10.1107/S1600536811037263 |pmid=22058680|pmc=3201338|bibcode=2011AcCrE..67I..56L }} {{chem2|KRbYbTi(PO4)3}}.{{cite journal |last=Gustafsson |first=Joacim C. M. |author2=Stefan T. Norberg |author3=Göran Svensson |year=2006 |title=The langbeinite type Rb2TiY(PO4)3 |journal=Acta Crystallographica Section E |volume=62 |issue=7 |pages=i160–i162 |doi=10.1107/S1600536806021635|bibcode=2006AcCrE..62I.160G }} Sodium barium diiron tris-(phosphate) ({{chem2|NaBaFe2(PO4)3}}) is yet another variation with the same structure but differently charged ions.{{cite journal |last=Hidouri |first=Mourad |author2=Hasna Jerbi |author3=Mongi Ben Amara |year=2008 |title=The iron phosphate NaBaFe2(PO4)3 |journal=Acta Crystallographica Section E |volume=64 |issue=8 |pages=i51 |doi=10.1107/S1600536808023040 |pmid=21202994 |pmc=2961906|bibcode=2008AcCrE..64I..51H }} Most phosphates of this kind of formula do not form langbeinites, instead crystallise in the NASICON structure with archetype {{chem2|Na3Zr2(PO4)(SiO4)2}}.

A langbeinite with arsenate is known to exist by way of {{chem2|K2ScSn(AsO4)3}}.{{cite journal |last=Harrison |first=William T. A. |year=2010 |title=K2ScSn(AsO4)3: an arsenate-containing langbeinite |journal=Acta Crystallographica Section C |volume=66 |issue=7 |pages=i82–i84 |doi=10.1107/S0108270110021670 |pmid=20603547 |bibcode=2010AcCrC..66I..82H |url=http://repositorio.unicamp.br/jspui/handle/REPOSIP/198934}}

Properties

=Physical properties=

Langbeinite-family crystals can show ferroelectric or ferroelastic properties. Diammonium dicadmium sulfate identified by Jona and Pepinsky{{cite journal |last=Jona |first=F. |author2=R. Pepinsky |year=1956 |title=Ferroelectricity in the Langbeinite System |journal=Physical Review |volume=103 |issue=4 |pages=1126 |doi=10.1103/PhysRev.103.1126 |bibcode=1956PhRv..103.1126J}} with a unit cell size of 10.35 Å becomes ferroelectric when the temperature drops below 95 K.{{cite journal |last=McDowell |first=C. A. |author2=P. Raghunathan |author3=R. Srinivasan |year=1975 |title=Proton N.M.R. study of the dynamics of the ammonium ion in ferroelectric langbeinite, (NH4)2Cd2(SO4)3 |journal=Molecular Physics |volume=29 |issue=3 |pages=815–824 |doi=10.1080/00268977500100721 |bibcode=1975MolPh..29..815M}} The phase transition temperature is not fixed, and can vary depending on the crystal or history of temperature change. So for example the phase transition in diammonium dicadmium sulfate can occur between 89 and 95 K.{{cite web |url=http://ir.lib.hiroshima-u.ac.jp/metadb/up/ZZT00003/200703/Ferroelectrics_337_85.pdf |title=Structural Study of Langbeinite-type ((NH4)2Cd2(SO4)3) Crystal in the High Temperature Phase |last=Moriyoshi |first=C. |author2=E. Magome |author3=K. Itoh |date=28 March 2007 |website=IMF-11 |access-date=24 June 2013}} Under pressure the highest phase transition temperature increases. ∂T/∂P = 0.0035 degrees/bar. At 824 bars there is a triple point with yet another transition diverging at a slope of ∂T/∂P = 0.103 degrees/bar.{{cite journal |last=Glogarová |first=M. |author2=C. Frenzel |author3=E. Hegenbarth |year=1972 |title=The Behaviour of (NH4)2Cd2(SO4)3 under Pressure |journal=Physica Status Solidi B |volume=53 |issue=1 |pages=369–372 |doi=10.1002/pssb.2220530139 |bibcode=1972PSSBR..53..369G}} For dipotassium dimanganese sulfate pressure causes the transition to rise at the rate of 6.86 °C/kbar. The latent heat of the transition is 456 cal/mol.{{cite journal |last=Hikita |first=Tomoyuki |author2=Makoto Kitabatake |author3=Takuro Ikeda |year=1979 |title=Hydrostatic Pressure Effect on the Phase Transition of K2Mn2(SO4)3 |journal=Journal of the Physical Society of Japan |volume=46 |issue=2 |pages=695–696 |doi=10.1143/JPSJ.46.695 |bibcode=1979JPSJ...46..695H}}

Dithallium dicadmium sulfate was shown to be ferroelectric in 1972.{{cite journal |last=Brzina |first=B. |author2=M. Glogarová |year=1972 |title=New ferroelectric langbeinite Tl2Cd2(SO4)3 |journal=Physica Status Solidi A |volume=11 |issue=1 |pages=K39–K42 |doi=10.1002/pssa.2210110149 |bibcode=1972PSSAR..11...39.}}

Dipotassium dicadmium sulfate is thermoluminescent with stronger outputs of light at 350 and 475 K. This light output can be boosted forty times with a trace amount of samarium.{{cite journal |last=Deshmukh |first=B. T. |author2=S. V. Bodade |author3=S. V. Moharil |year=1986 |title=Thermoluminescence of K2Cd2(SO4)3 |journal=Physica Status Solidi A |volume=98 |issue=1 |pages=239–246 |doi=10.1002/pssa.2210980127 |bibcode=1986PSSAR..98..239D}} Dipotassium dimagnesium sulfate doped with dysprosium develops thermoluminescence and mechanoluminescence after being irradiated with gamma rays.{{cite journal |last=Panigrahi |first=A. K. |author2=Dhoble, S. J. |author3=Kher, R. S. |author4=Moharil, S. V. |year=2003 |title=Thermo and mechanoluminescence of Dy3+ activated { K2Mg2(SO4)3 phosphor |journal=Physica Status Solidi A |volume=198 |issue=2 |pages=322–328 |doi=10.1002/pssa.200306605 |bibcode=2003PSSAR.198..322P}} Since gamma rays occur naturally, this radiation induced thermoluminescence can be used to date evaporites in which langbeinite can be a constituent.{{cite journal |last=Léost |first=I. |author2=Féraud, G. |author3=Blanc-Valleron, M. M. |author4=Rouchy, J. M. |year=2001 |title=First absolute dating of Miocene Langbeinite evaporites by 40Ar/39Ar laser step-heating: [K2Mg2(SO4)3] Stebnyk Mine (Carpathian Foredeep Basin) |journal=Geophysical Research Letters |volume=28 |issue=23 |pages=4347–4350 |doi=10.1029/2001GL013477 |bibcode=2001GeoRL..28.4347L |doi-access=free}}

At higher temperatures the crystals take on cubic form, whereas at the lowest temperatures they can transform to an orthorhombic crystal group. For some types there are two more phases, and as the crystal is cooled it goes from cubic, to monoclinic, to triclinic to orthorhombic. This change to higher symmetry on cooling is very unusual in solids.{{cite journal |last=Franke |first=V. |author2=E. Hegenbarth |author3=B. Březina |year=1975 |title=Specific heat measurement on Tl2Cd2(SO4)3 |journal=Physica Status Solidi A |volume=28 |issue=1 |pages=K77–K80 |doi=10.1002/pssa.2210280165 |bibcode=1975PSSAR..28...77F}} For some langbeinites only the cubic form is known, but that may be because it has not been studied at low enough temperatures yet. Those that have three phase transitions go through these crystallographic point groups: P213 – P21 – P1 – P212121, whereas the single phase change crystals only have P213 – P212121.

{{chem2|K2Cd2(SO4)3}} has a transition temperature above room temperature, so that it is ferroelectric in standard conditions. The orthorhombic cell size is a=10.2082 Å, b=10.2837 Å, c=10.1661 Å.{{cite journal |last=Abrahams |first=S. C. |author2=Bernstein, J. L. |year=1977 |title=Piezoelectric langbeinite-type K2Cd2(SO4)3: Room temperature crystal structure and ferroelastic transformation |journal=The Journal of Chemical Physics |volume=67 |issue=5 |page=2146 |doi=10.1063/1.435101 |bibcode=1977JChPh..67.2146A}}

Where the crystals change phase there is a discontinuity in the heat capacity. The transitions may show thermal hysteresis.{{cite journal |last=Cao |first=Hongjie |author2=Dalley, N. Kent |author3=Boerio-Goates, Juliana |year=1993 |title=Calorimetric and structural studies of langbeinite-type Tl2Cd2(SO4)3 |journal=Ferroelectrics |volume=146 |issue=1 |pages=45–56 |doi=10.1080/00150199308008525|bibcode=1993Fer...146...45C }}

Different cations can be substituted so that for example {{chem2|K2Cd2(SO4)3}} and {{chem2|Tl2Cd2(SO4)3}} can form solid solutions for all ratios of thallium and potassium. Properties such as the phase transition temperature and unit cell sizes vary smoothly with the composition.{{cite journal |last=Sutera |first=A. |author2=Nassau, K. |author3=Abrahams, S. C. |year=1981 |title=Phase-transition variation with composition in solid solutions of K2Cd2(SO4)3 with Tl2Cd2(SO4)3 |journal=Journal of Applied Crystallography |volume=14 |issue=5 |pages=297–299 |doi=10.1107/S0021889881009412|bibcode=1981JApCr..14..297S }}

Langbeinites containing transition metals can be coloured. For example, cobalt langbeinite shows a broad absorption around 555 nm due to the cobalt 4T1g(F)→4T1g(P) electronic transition.{{cite journal |last=Percival |first=M. J. L. |year=1990 |title=Optical Absorption Spectroscopy of Doped Materials: The P213-P212121 Phase Transition in K2(Cd0.98Co0.02)2(SO4)3 |journal=Mineralogical Magazine|volume=54|issue=377|pages=525–535 |doi=10.1180/minmag.1990.054.377.01 |bibcode=1990MinM...54..525P|s2cid=96797382 }}

The enthalpy of formation (ΔfHm) for solid {{chem2|(NH4)2Cd2(SO4)3}} at 298.2 K is {{val|−3031.74|0.08|u=kJ/mol}}, and for {{chem2|K2Cd2(SO4)3}} it is {{val|-3305.52|0.17|u=kJ/mol}}.{{cite journal |last=Zhou |first=Ya-Ping |author2=Rui, Zhang |author3=Hong-Wen, Wan |author4=Zheng-Kun, Zhan |author5=Ming-Fei, Xu |date=March 2001 |title=Thermochemical Studies on the Langbeinite-Type Double Sulfate Salts，(NH4)2Cd2(SO4)3 and K2Cd2(SO4)3 |journal=Acta Physico-Chimica Sinica |volume=17 |issue=3 |page=247 |doi=10.3866/PKU.WHXB20010312 |url=http://www.whxb.pku.edu.cn/EN/abstract/abstract24330.shtml |language=Chinese |doi-access=free}}

=Sulfates=

class="wikitable"

|+ Properties of langbeinites with sulfate anions

! scope=col rowspan=2 | Formula

! scope=col rowspan=2 | Weight (g/mol)

! scope=col rowspan=2 | Comment / Symmetries

! scope=col colspan=3 | Transition temperature (K)

! scope=col rowspan=2 | Density

! scope=col rowspan=2 | Cell size (Å)

! scope=col rowspan=2 | Refractive index

scope=col | 1

! scope=col | 2

! scope=col | 3{{cite journal |last=Boerio-Goates |first=Juliana |author2=Johanne I. Artman |author3=Brian F. Woodfield |year=1990 |title=Heat capacity studies of phase transitions in langbeinites II. K2Mg2(SO4)3 |journal=Physics and Chemistry of Minerals |volume=17 |issue=2 |pages=173 |doi=10.1007/BF00199670 |bibcode=1990PCM....17..173B |s2cid=95991273}}

{{chem2|Na2Mg2(SO4)3}}

|382.78

|3 phases, 1–2, >3

|250

|350

|575{{cite journal |last1=Trussov |first1=I. A. |last2=Male |first2=L. L. |last3=Sanjuan |first3=M. L. |last4=Orera |first4=A. |last5=Slater |first5=P. R. |title=Understanding the complex structural features and phase changes in Na2Mg2(SO4)3: A combined single crystal and variable temperature powder diffraction and Raman spectroscopy study |journal=Journal of Solid State Chemistry |date=April 2019 |volume=272 |pages=157–165 |doi=10.1016/j.jssc.2019.02.014|bibcode=2019JSSCh.272..157T |s2cid=104364241 |url=http://zaguan.unizar.es/record/87694 |hdl=10261/192264 |hdl-access=free }}

|

|

|

{{chem2|K2Mg2(SO4)3}}

|414.99

|4 phases langbeinite

|51

|54.9

|63.8

|2.832{{cite journal |last=Speer |first=D. |author2=Salje, E. |year=1986 |title=Phase transitions in langbeinites I: Crystal chemistry and structures of K-double sulfates of the langbeinite type M3++K2(SO4)3, M++=Mg, Ni, Co, Zn, Ca |journal=Physics and Chemistry of Minerals |volume=13 |issue=1 |pages=17–24 |doi=10.1007/BF00307309 |bibcode=1986PCM....13...17S|s2cid=96828689}}

|9.9211{{cite journal |last1=Burkov |first1=V. I. |last2=Perekalina |first2=Z. B. |year=2001 |title=Gyrotropy of Cubic Langbeinite Crystals |journal=Inorganic Materials |volume=37 |issue=3 |pages=203–212 |doi=10.1023/A:1004165926149 |s2cid=92506742}}

|1.536{{cite tech report |last1=Swanson |first1=H. E. |last2=McMurdie |first2=H. F. |last3=Morris |first3=M. C. |last4=Evans |first4=E. H. |date=June 1968 |title=Standard X-ray Diffraction Powder Patterns |series= NBS Monograph 5 |volume=Section 6 – Data for 60 Substances |type=Monograph |publisher=National Bureau of Standards |url=https://nvlpubs.nist.gov/nistpubs/Legacy/MONO/nbsmonograph25-6.pdf |access-date=2021-03-23 |doi=10.6028/NBS.MONO.25-6 |page=40|doi-access=free }}

{{chem2|Rb2Mg2(SO4)3}}

|507.73

|made

|

|

|

|3.367{{cite tech report |last1=Swanson |first1=H. E. |last2=McMurdie |first2=H. F. |last3=Morris |first3=M. C. |last4=Evans |first4=E. H. |date=September 1969 |title=Standard X-ray Diffraction Powder Patterns |series= NBS Monograph 5 |volume=Section 7 – Data for 81 Substances |type=Monograph |publisher=National Bureau of Standards |location=Washington D.C. |url=https://nvlpubs.nist.gov/nistpubs/Legacy/MONO/nbsmonograph25-7.pdf |access-date=2021-03-24 |doi=10.6028/NBS.MONO.25-7 |page=50|doi-access=free }}

|10.0051{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=50}}

|1.556

{{chem2|Cs2Mg2(SO4)3}}

|602.61

|no compound{{cite web |url=http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA332686 |archive-url=https://web.archive.org/web/20130706024403/http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA332686 |url-status=dead |archive-date=July 6, 2013 |title=Property Predictions for Multicomponent Compounds |last=Kiselyova |first=Nadezhda |date=September 1997 |publisher=Russian Academy of Sciences |access-date=6 July 2013}}

|

|

|

|

|

|

{{chem2|(NH4)2Mg2(SO4)3}}

|372.87

|Efremovite{{cite web |title=Efremovite: Efremovite mineral information and data |url=https://www.mindat.org/min-1355.html |website=www.mindat.org}}

|241

|220

|

|2.49

|9.979

|

{{chem2|Tl2Mg2(SO4)3}}

|745.56

|≥3 phase

|

|227.8{{cite journal |last=Kahrizi |first=Mojtaba |author2=Steinitz, M. O. |year=1988 |title=Phase transitions and thermal expansion in langbeinite type compounds |journal=Solid State Communications |volume=66 |issue=4 |pages=375–378 |doi=10.1016/0038-1098(88)90860-5 |bibcode=1988SSCom..66..375K}}

|330.8

|

|

|

{{chem2|K2CaMg(SO4)3}}

|430.77

|made

|

|

|

|2.723{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=37}}

|10.1662

|1.525

{{chem2|K2Ca2(SO4)3}}

|446.54

|4 phases calciolangbeinite{{cite web |title=Calciolangbeinite |url=http://www.handbookofmineralogy.org/pdfs/calciolangbeinite.pdf |publisher=Mineralogical Society of America |access-date=29 February 2016 |date=13 June 2015}}{{cite web |title=Calciolangbeinite: Mineral information, data and localities. |url=https://www.mindat.org/min-42383.html |website=www.mindat.org}}{{Cite journal |last1=Pekov |first1=Igor V. |last2=Zubkova |first2=Natalia V. |last3=Galuskina |first3=Irina O. |last4=Kusz |first4=Joachim |last5=Koshlyakova |first5=Natalia N. |last6=Galuskin |first6=Evgeny V. |last7=Belakovskiy |first7=Dmitry I. |last8=Bulakh |first8=Maria O. |last9=Vigasina |first9=Marina F. |last10=Chukanov |first10=Nikita V. |last11=Britvin |first11=Sergey N. |date=2022-01-28 |title=Calciolangbeinite- O , a natural orthorhombic modification of K 2 Ca 2 (SO 4 ) 3 , and the langbeinite–calciolangbeinite solid-solution system |url=https://www.cambridge.org/core/product/identifier/S0026461X21000955/type/journal_article |journal=Mineralogical Magazine |volume=86 |issue=4 |language=en |pages=557–569 |doi=10.1180/mgm.2021.95 |bibcode=2022MinM...86..557P |s2cid=246406414 |issn=0026-461X}}

|457

|

|

|2.69 2.683{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=39}}

|10.429Å a=10.334 b=10.501 c=10.186

|Nα=1.522 Nβ=1.526 Nγ=1.527

{{chem2|Rb2Ca2(SO4)3}}

|539.28

|2 phases

|183

|

|

|3.034{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=48}}

|10.5687

|1.520

{{chem2|Cs2Ca2(SO4)3}}

|634.15

|

|

|

|

|3.417{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=12}}{{cite journal |last=Gattow |first=G. |author2=Zemann, J. |year=1958 |title=Über Doppelsulfate vom Langbeinit-Typ, A2+B22+(SO4)3 |journal=Zeitschrift für Anorganische und Allgemeine Chemie |volume=293 |issue=5–6 |pages=233–240 |doi=10.1002/zaac.19582930502 |language=de}}

|10.7213

|1.549

{{chem2|Tl2Ca2(SO4)3}}

|

|no compound

|

|

|

|

|

|

{{chem2|(NH4)2Ca2(SO4)3}}

|404.42

|made

|158

|

|

|2.297{{cite tech report |last1=Swanson |first1=H. E. |last2=McMurdie |first2=H. F. |last3=Morris |first3=M. C. |last4=Evans |first4=E. H. |date=September 1970 |title=Standard X-ray Diffraction Powder Patterns |series= NBS Monograph 5 |volume=Section 8 – Data for 81 Substances |type=Monograph |publisher=National Bureau of Standards |location=Washington D.C. |url=https://nvlpubs.nist.gov/nistpubs/Legacy/MONO/nbsmonograph25-8.pdf |access-date=2021-03-24 |doi=10.6028/NBS.MONO.25-8 |page=7|doi-access=free }}

|10.5360{{harvnb|Swanson|McMurdie|Morris|Evans|1970|p=7}}

|1.532

{{chem2|(NH4)2V2(SO4)3}}

|colour clear green

|

|

|

|

|2.76[http://crystdb.nims.go.jp/crystdb/search-list?search=Search+materials&condition_type=chemical_system&need_more_value=&need_more_type=prototype_number&condition_value=N+H+S+V+O&isVisiblePeriodicTable=false&substance_id=20195&search-type=search-materials NIMS search result]

|10.089{{cite journal |journal=Bulletin de la Société Chimique de France: Première Partie |date=July 1977 |pages=653–655 |issue=7/8 |author1=Tudo, Joseph |author2=Laplace, Laplace |title=Les sulfates doubles de vanadium et d'ammonium. I. Sur la schoenite de vanadium II et ammonium}}

|

{{anchor|manganolangbeinite}}{{chem2|K2Mn2(SO4)3}}

|476.26

| manganolangbeiniteBellanca, A. (1947). Sulla simmetria della manganolangbeinite/ Atti Accad. Nazi. Lincei Rend. Classe Sci. Fis. Mat. Nat. 2, 451–455.
2 phases
pale pink

|191

|

|

|3.02

|10.014
(orthorhombic)
a=10.081, b=10.108, c=10.048 Å{{cite journal |last=Yamada |first=Noboru |author2=Maeda, Masaki |author3=Adachi, Hideaki |year=1981 |title=Structures of langbeinite-type dipotassium dimanganese sulfate in cubic and orthorhombic phases |journal=Journal of the Physical Society of Japan |volume=50 |issue=3 |pages=907–913 |doi=10.1143/jpsj.50.907 |bibcode = 1981JPSJ...50..907Y }}

|1.576{{harvnb|Swanson|McMurdie|Morris|Evans|1968|p=43}}

{{chem2|Rb2Mn2(SO4)3}}

|569

|made{{cite journal |last=Swain |first=Diptikanta |author2=Guru Row, T. N. |year=2006 |title=Rb2Mn2(SO4)3, a new member of the langbeinite family |journal=Acta Crystallographica Section E |volume=62 |issue=6 |pages=m138–m139 |doi=10.1107/S1600536806019490|bibcode=2006AcCrE..62R.138S }}

|

|

|

|3.546{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=52}}

|10.2147

|1.590

{{chem2|Cs2Mn2(SO4)3}}

|663.87

|predicted

|

|

|

|

|

|

{{chem2|(NH4)2Mn2(SO4)2}}

|434.14

|made

|

|

|

|2.72[http://crystdb.nims.go.jp AtomWork materials database at NIMS]

|10.1908{{Cite book |last=Hikita |first=T. |year=2005 |title=(NH4)2SO4 family ... K3BiCl6·2KCl·KH3F4 |chapter=43B-6 (NH4)2Mn2(SO4)3-(NH4)2Mn2(SeO4)3 |volume=36B2 |pages=1–3 |doi=10.1007/10552342_84 |isbn=9783540313533 |work=Inorganic Substances other than Oxides |series=Landolt-Börnstein - Group III Condensed Matter}}

|

{{chem2|Tl2Mn2(SO4)3}}

|806.83

|made

|

|

|

|5.015{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=76}}

|10.2236

|1.722

{{chem2|K2Fe2(SO4)3}}

|478.07

|made

|?130

|

|

|

|

|

{{chem2|Rb2Fe2(SO4)3}}

|

|predicted

|

|

|

|

|

|

{{chem2|Tl2Fe2(SO4)3}}

|808.64

|exists

|

|

|

|

|

|

{{chem2|(NH4)2Fe2(SO4)3}}

|435.95

|mineral ferroefremovite

|

|

|

|2.84

|10.068

|1.574{{cite journal |last1=Kasatkin |first1=Anatoly V. |last2=Plášil |first2=Jakub |last3=Škoda |first3=Radek |last4=Campostrini |first4=Italo |last5=Chukanov |first5=Nikita V. |last6=Agakhanov |first6=Atali A. |last7=Karpenko |first7=Vladimir Yu. |last8=Belakovskiy |first8=Dmitriy I. |title=Ferroefremovite, (NH4)2Fe2+2(SO4)3, a new mineral from Solfatara di Pozzuoli, Campania, Italy |journal=The Canadian Mineralogist |date=14 December 2020 |volume=59 |pages=59–68 |doi=10.3749/canmin.1900085|s2cid=230591609 }}

{{chem2|K2Co2(SO4)3}}

|484.25

|2 phases
deep purple

|126

|

|

|3.280

|9.9313

|1.608{{harvnb|Swanson|McMurdie|Morris|Evans|1968|p=35}}

{{chem2|Rb2Co2(SO4)3}}

|576.99

|made

|

|

|

|3.807{{harvnb|Swanson|McMurdie|Morris|Evans|1970|p=59}}

|10.0204

|1.602

{{chem2|Cs2Co2(SO4)3}}

|671.87

|

|

|

|

|

|

|

{{chem2|(NH4)2Co2(SO4)3}}

|442.13

|made

|

|

|

|2.94

|9.997

|

{{chem2|Tl2Co2(SO4)3}}

|813.82

|made

|

|

|

|5.361{{harvnb|Swanson|McMurdie|Morris|Evans|1970|p=85}}

|10.0312

|1.775

{{chem2|K2Ni2(SO4)3}}

|483.77

|made{{cite journal |last=Jayakumar |first=V. S. |author2=I. Hubert Joe |author3=G. Aruldhas |year=1995 |title=IR and single crystal Raman spectra of langbeinities M2Ni2(SO4)3 (M = NH4, K) |journal=Ferroelectrics |volume=165 |issue=1 |pages=307–318 |doi=10.1080/00150199508228311|bibcode=1995Fer...165..307J }} light greenish yellow

|

|

|

|3.369

|9.8436{{harvnb|Swanson|McMurdie|Morris|Evans|1968|p=46}}

|1.620

{{chem2|Rb2Ni2(SO4)3}}

|576.51

|made

|

|

|

|3.921{{harvnb|Swanson|McMurdie|Morris|Evans|1970|p=72}}

|9.9217

|1.636

{{chem2|Cs2Ni2(SO4)3}}

|671.39

|predicted

|

|

|

|

|

|

{{chem2|(NH4)2Ni2(SO4)3}}

|441.65

|made

|160

|

|

|3.02

|9.904

|

{{chem2|Tl2Ni2(SO4)3}}

|814.34

|predicted

|

|

|

|

|

|

{{chem2|Rb2Cu2(S04)3}}

|

|predicted

|

|

|

|

|

|

{{chem2|Cs2Cu2(S04)3}}

|

|predict not

|

|

|

|

|

|

{{chem2|Tl2Cu2(S04)3}}

|

|predicted

|

|

|

|

|

|

{{chem2|K2Zn2(SO4)3}}

|497.1

|4 phases

|75

|138

|

|3.376

|9.9247{{harvnb|Swanson|McMurdie|Morris|Evans|1968|p=54}}

|1.592

{{chem2|Rb2Zn2(S04)3}}

|

|predicted

|

|

|

|

|

|

{{chem2|Cs2Zn2(S04)3}}

|

|predict not

|

|

|

|

|

|

{{chem2|Tl2Zn2(S04)3}}

|

|predicted

|

|

|

|

|

|

{{chem2|K2Cd2(SO4)3}}

|591.21

|2 phases

|432

|

|

|2.615 3.677{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=34}}

|a=10.212 b=10.280 c=10.171

|Nα=1.588 Nγ=1.592

{{chem2|Rb2Cd2(SO4)3}}

|683.95

|4 phases

|66

|103

|129

|4.060

|10.3810

|1.590{{harvnb|Swanson|McMurdie|Morris|Evans|1969|p=45}}

{{chem2|(NH4)2Cd2(SO4)3}}

|549.09

|4 phases

|

|

|95

|3.288

|10.3511

|

{{chem2|Tl2Cd2(SO4)3}}

|921.78

|4 phases

|92

|120

|132

|5.467

|10.3841

|1.730{{harvnb|Swanson|McMurdie|Morris|Evans|1970|p=83}}

Fluoroberyllates

class="wikitable"

|+ Properties of langbeinites with fluoroberyllate ({{chem2|BeF4(2-)}}) anion

scope=col | Formula

! scope=col | Weight (g/mol)

! scope=col | Cell size (Å)

! scope=col | Volume

! scope=col | Density

! scope=col | Comment

{{chem2|K2Mn2(BeF4)3}}

|

|

|

|

|4 phases transition at 213

{{chem2|K2Mg2(BeF4)3}}{{cite journal |last1=Le Fur |first1=Y. |last2=Aléonard |first2=S |title=Etude d'orthofluoroberyllates MeI2MeII2(BeF4)3 de structure langbeinite |journal=Materials Research Bulletin |date=August 1969 |volume=4 |issue=8 |pages=601–615 |doi=10.1016/0025-5408(69)90121-4}}

|

|9.875

|962.8

|1.59

|

{{chem2|(NH4)2Mg2(BeF4)3}}

|

|9.968

|

|1.37

|

{{chem2|KRbMg2(BeF4)3}}

|

|9.933

|

|1.72

|

{{chem2|Rb2Mg2(BeF4)3}}

|

|9.971

|

|1.91

|

{{chem2|Tl2Mg2(BeF4)3}}

|

|9.997

|

|2.85

|

{{chem2|K2Ni2(BeF4)3}}

|

|9.888

|

|1.86

|

{{chem2|Rb2Ni2(BeF4)3}}

|

|9.974

|

|2.19

|

{{chem2|Tl2Ni2(BeF4)3}}

|

|9.993

|

|3.13

|

{{chem2|K2Co2(BeF4)3}}

|

|9.963

|988

|1.82

|

{{chem2|(NH4)2Co2(BeF4)3}}

|

|10.052

|

|1.61

|

{{chem2|Rb2Co2(BeF4)3}}

|

|10.061

|

|2.14

|

{{chem2|Tl2Co2(BeF4)3}}

|

|10.078

|

|3.05

|

{{chem2|RbCsCo2(BeF4)3}}

|

|10.115

|

|2.28

|

{{chem2|K2Zn2(BeF4)3}}

|

|9.932

|

|1.89

|

{{chem2|(NH4)Zn2(BeF4)3}}

|

|10.036

|

|1.67

|

{{chem2|Rb2Zn2(BeF4)3}}

|

|10.035

|

|2.20

|

{{chem2|Tl2Zn2(BeF4)3}}

|

|10.060

|

|3.14

|

{{chem2|RbCsZn2(BeF4)3}}

|

|10.102

|

|2.36

|

{{chem2|K2Mn2(BeF4)3}}

|

|10.102

|

|1.72

|

{{chem2|KRbMn2(BeF4)3}}

|

|10.187

|

|1.82

|

{{chem2|(NH4)2Mn2(BeF4)3}}

|

|10.217

|

|1.50

|

{{chem2|Rb2Mn2(BeF4)3}}

|

|10.243

|

|2.00

|

{{chem2|Tl2Mn2(BeF4)3}}

|

|10.255

|

|2.87

|

{{chem2|RbCsMn2(BeF4)3}}

|

|10.327

|

|2.12

|

{{chem2|Cs2Mn2(BeF4)3}}

|

|10.376

|

|2.26

|

{{chem2|K2MnCd(BeF4)3}}

|

|10.133

|

|1.92

|

{{chem2|KRbMnCd(BeF4)3}}

|

|10.220

|

|2.04

|

{{chem2|Rb2MnCd(BeF4)3}}

|

|10.133

|

|1.92

|

{{chem2|RbCsMnCd(BeF4)3}}

|

|10.380

|

|2.28

|

{{chem2|Cs2MnCd(BeF4)3}}

|

|10.451

|

|2.41

|

{{chem2|(NH4)2Cd2(BeF4)3}}

|

|10.342

|

|1.87

|

{{chem2|Rb2Cd2(BeF4)3}}

|

|10.385

|

|2.32

|

{{chem2|Tl2Cd2(BeF4)3}}

|

|10.402

|

|3.16

|

{{chem2|RbCsCd2(BeF4)3}}

|

|10.474

|

|2.43

|

{{chem2|Cs2Cd2(BeF4)3}}

|

|10.558

|

|2.53

|

{{chem2|RbCsCdCa(BeF4)3}}

|

|10.501

|

|2.15

|

{{chem2|Rb2Ca2(BeF4)3}}

|

|10.480

|

|1.74

|

{{chem2|RbCsCa2(BeF4)3}}

|

|10.583

|

|1.86

|

{{chem2|Cs2Ca2(BeF4)3}}

|

|10.672

|

|1.98

|

{{chem2|Cs2Mg2(BeF4)3}}

|

|

|

|

|does not exist

Phosphates

class="wikitable"

|+ Properties of langbeinites with phosphate ({{chem2|PO4(2-)}}) anion

!scope=col | Formula

!scope=col | Weight (g/mol)

!scope=col | Cell size (Å)

!scope=col | Density

!scope=col | Comment

!ref

{{chem2|LiCs2Y2(PO4)3}}

|735.48

|10.5945

|4.108

|

|{{cite journal |last1=Shen |first1=Y. |last2=Yang |first2=Y. |last3=Zhao |first3=S. |last4=Li |first4=X. |last5=Ding |first5=Q. |last6=Li |first6=Y. |last7=Liu |first7=S. |last8=Lin |first8=Z. |last9=Luo |first9=J. |year=2018 |title=CCDC Number: 1862371 |url=https://www.ccdc.cam.ac.uk/structures/search?pid=ccdc:1862371&issn=&id=doi:10.1021/acs.inorgchem.8b02491&sid=ACS |journal=Inorganic Chemistry |language=en |volume=57 |issue=21 |pages=13087–13091 |doi=10.1021/acs.inorgchem.8b02491 |pmid=30299091 |s2cid=52941066}}

{{chem2|LiRb2Y2(PO4)3}}

|

|

|

|non-linear optical

|{{cite journal |last1=Shen |first1=Yaoguo |last2=Liu |first2=Zhiqun |last3=Yu |first3=Hualiang |last4=Zhou |first4=Bi |date=April 2020 |title=Aliovalent-substituted synthesis for a non-centrosymmetric phosphate with enhanced nonlinear-optical response |journal=Journal of Solid State Chemistry |volume=288 |pages=121361 |bibcode=2020JSSCh.28821361S |doi=10.1016/j.jssc.2020.121361 |s2cid=216369312}}

{{chem2|K2YTi(PO4)3}}

|578.25

|10.1053

|3.192

|

|

{{chem2|K2ErTi(PO4)3}}

|584.03

|10.094

|3.722

|

|

{{chem2|K2YbTi(PO4)3}}

|499.89

|10.1318

|3.772

|

|

{{chem2|K2CrTi(PO4)3}}

|462.98

|9.8001

|3.267

|

|

{{chem2|(NH4)(H3O)Ti^{III}Ti^{IV}(PO4)3}}

|417.71

|9.9384

|

|

|{{cite journal |last=Fu |first=Yun-Long |author2=Xu, Zhi-Wei |author3=Ren, Jia-Lin |author4=Ng, Seik Weng |year=2005 |title=Langbeinite-type mixed-valence (NH4)(H3O)Ti[III]Ti[IV](PO4)3 |journal=Acta Crystallographica Section E |volume=61 |issue=8 |pages=i158–i159 |doi=10.1107/S1600536805021392}}

{{chem2|K2Ti2(PO4)3}}

|458.84

|9.8688

|

|Also {{chem2|K_{2−x} }}; dark blue

|{{cite journal |last1=Leclaire |first1=A. |last2=Benmoussa |first2=A. |last3=Borel |first3=M. M. |last4=Grandin |first4=A. |last5=Raveau |first5=B. |date=February 1989 |title=K2−xTi2(PO4)3 with 0 ≤ x ≤ 0.5: A mixed-valence nonstoichiometric titanophosphate with the langbeinite structure |journal=Journal of Solid State Chemistry |volume=78 |issue=2 |pages=227–231 |bibcode=1989JSSCh..78..227L |doi=10.1016/0022-4596(89)90101-1}}

{{chem2|Rb2Ti2(PO4)3}}

|551.58

|9.9115

|

|

|

{{chem2|Tl2Ti2(PO4)3}}

|789.41

|9.9386

|

|

|

{{chem2|Na2FeTi(PO4)3}}

|

|9.837

|

|

|{{cite journal |last1=Isasi |first1=J |date=2 August 2000 |title=Synthesis, structure and conductivity study of new monovalent phosphates with the langbeinite structure |journal=Solid State Ionics |volume=133 |issue=3–4 |pages=303–313 |doi=10.1016/S0167-2738(00)00677-9}}

{{chem2|Na2CrTi(PO4)3}}

|

|9.775

|

|

|

{{chem2|K2Mn0.5Ti1.5(PO4)3}}

|

|9.903

|3.162

|dark brown

|{{cite journal |last1=Ogorodnyk |first1=Ivan V. |last2=Zatovsky |first2=Igor V. |last3=Slobodyanik |first3=Nikolay S. |last4=Baumer |first4=Vyacheslav N. |last5=Shishkin |first5=Oleg V. |date=November 2006 |title=Synthesis, structure and magnetic properties of new phosphates K2Mn0.5Ti1.5(PO4)3 and K2Co0.5Ti1.5(PO4)3 with the langbeinite structure |journal=Journal of Solid State Chemistry |volume=179 |issue=11 |pages=3461–3466 |bibcode=2006JSSCh.179.3461O |doi=10.1016/j.jssc.2006.07.015}}

{{chem2|K2Co0.5Ti1.5(PO4)3}}

|

|9.844

|3.233

|dark brown

|

{{chem2|Rb4NiTi3(PO4)6}}

|1113.99÷2

|9.9386

|

|

|{{cite journal |last1=Strutynska |first1=Nataliia Yu. |last2=Bondarenko |first2=Marina A. |last3=Ogorodnyk |first3=Ivan V. |last4=Zatovsky |first4=Igor V. |last5=Slobodyanik |first5=Nikolay S. |last6=Baumer |first6=Vyacheslav N. |last7=Puzan |first7=Anna N. |date=May 2015 |title=Interaction in the molten system Rb2 O-P2 O5 -TiO -NiO. Crystal structure of the langbeinite-related Rb2Ni0.5Ti1.5(PO4) |journal=Crystal Research and Technology |volume=50 |issue=7 |pages=549–555 |doi=10.1002/crat.201500050 |s2cid=98316028}}

{{chem2|K2AlTi(PO4)3}}

|437.96

|9.7641

|3.125

|colourless

|{{cite journal |last=Zhao |first=Dan |author2=Zhang, Hao |author3=Huang, Shu-Ping |author4=Zhang, Wei-Long |author5=Yang, Song-Lin |author6=Cheng, Wen-Dan |year=2009 |title=Crystal and band structure of K2AlTi(PO4)3 with the langbeinite-type structure |journal=Journal of Alloys and Compounds |volume=477 |issue=1–2 |pages=795–799 |doi=10.1016/j.jallcom.2008.10.124}}

K2TiYb(PO4)3

|

|

|

|

|{{Cite journal |last1=Ding |first1=Jimin |last2=Zhu |first2=Pengfei |last3=Li |first3=Ziqing |last4=Wang |first4=Zhenyan |last5=Ai |first5=Li |last6=Zhao |first6=Jianfu |last7=Yu |first7=Fapeng |last8=Duan |first8=Xiulan |last9=Jiang |first9=Huaidong |date=July 2021 |title=Synthesis, electronic structure and upconversion photoluminescence of langbeinite-type K2TiYb(PO4)3 microcrystals |url=https://linkinghub.elsevier.com/retrieve/pii/S0030402621011645 |journal=Optik |language=en |volume=244 |pages=167549 |bibcode=2021Optik.244p7549D |doi=10.1016/j.ijleo.2021.167549}}

{{chem2|Li2Zr2(PO4)3}}

|481.24

|

|

|

|{{cite journal |last=Chen |first=Shuang |author2=Hoffmann, Stefan |author3=Weichert, Katja |author4=Maier, Joachim |author5=Prots, Yurii |author6=Zhao, Jing-Tai |author7=Kniep, Rüdiger |year=2011 |title=Li(H2O)2−x[Zr2(PO4)3]: A Li-Filled Langbeinite Variant (x= 0) as a Precursor for a Metastable Dehydrated Phase (x= 2) |journal=Chemistry of Materials |volume=23 |issue=6 |pages=1601–1606 |doi=10.1021/cm103487w}}

NaZr2(PO4)3

|980,71

|10.2088

|3.06125

|negative thermal expansion 25-500 °C

|{{Cite journal |last=Marshenya |first=Sergey N. |last2=Scherbakov |first2=Alexey G. |last3=Dembitskiy |first3=Artem D. |last4=Golubnichiy |first4=Alexander A. |last5=Trussov |first5=Ivan A. |last6=Savina |first6=Aleksandra A. |last7=Kazakov |first7=Sergey M. |last8=Aksyonov |first8=Dmitry A. |last9=Antipov |first9=Evgeny V. |last10=Fedotov |first10=Stanislav S. |date=2024 |title=NaZr 2 (PO 4 ) 3 – a cubic langbeinite-type sodium-ion solid conductor |url=https://xlink.rsc.org/?DOI=D4DT02288B |journal=Dalton Transactions |language=en |doi=10.1039/D4DT02288B |issn=1477-9226}}

{{chem2|K2(Ce, ..., Lu)Zr(PO4)3}}

|594.45...629.3

|10.29668

|

|

|{{cite journal |last=Ogorodnyk |first=I. V. |author2=Zatovsky, I. V. |author3=Baumer, V. N. |author4=Slobodyanik, N. S. |author5=Shishkin, O. V. |year=2007 |title=Synthesis and crystal structure of langbeinite related mixed-metal phosphates K1.822Nd0.822Zr1.178(PO4)3 and K2LuZr(PO4)3 |journal=Crystal Research and Technology |volume=42 |issue=11 |pages=1076–1081 |bibcode=2007CryRT..42.1076O |doi=10.1002/crat.200710961 |s2cid=197180278}}

{{chem2|Rb2FeZr(PO4)3}}

|602.92

|10.1199

|

|

|{{cite journal |last=Trubach |first=I. G. |author2=Beskrovnyi, A. I. |author3=Orlova, A. I. |author4=Orlova, V. A. |author5=Kurazhkovskaya, V. S. |year=2004 |title=Synthesis and structural study of Rb2FeZr(PO4)3 phosphate with langbeinite structure |journal=Crystallography Reports |volume=49 |issue=6 |pages=895–898 |bibcode=2004CryRp..49..895T |doi=10.1134/1.1828132 |s2cid=101730864}}

{{chem2|K2FeZr(PO4)3}}

|510.18

|10.0554

|

|dark grey Note {{chem2|Na2FeZr(PO4)3}} is not a langbeinite.

|{{cite journal |last1=Orlova |first1=Albina I. |last2=Trubach |first2=Ilya G. |last3=Kurazhkovskaya |first3=Victoria S. |last4=Pertierra |first4=Pilar |date=July 2003 |title=Synthesis, characterization, and structural study of K2FeZrP3O12 with the langbeinite structure |journal=Journal of Solid State Chemistry |volume=173 |issue=2 |pages=314–318 |bibcode=2003JSSCh.173..314O |doi=10.1016/S0022-4596(03)00101-4}}{{cite journal |last1=Asabina |first1=E. A. |last2=Pet'kov |first2=V. I. |last3=Gobechiya |first3=E. R. |last4=Kabalov |first4=Yu. K. |last5=Pokholok |first5=K. V. |last6=Kurazhkovskaya |first6=V. S. |date=19 May 2009 |title=Synthesis and crystal structure of phosphates A2FeTi(PO4)3 (A = Na, Rb) |journal=Russian Journal of Inorganic Chemistry |volume=53 |issue=1 |pages=40–47 |doi=10.1134/S0036023608010075 |s2cid=96452463}}

{{chem2|K2YZr(PO4)3}}

|543.24

|10.3346

|

|random {{chem2|Y}} and {{chem2|Zr}}

|{{cite journal |last1=Wulff |first1=H. |last2=Guth |first2=U. |last3=Loescher |first3=B. |date=10 January 2013 |title=The Crystal Structure of K2REZr(PO4)3(RE = Y, Gd) Isotypic with Langbeinite |journal=Powder Diffraction |volume=7 |issue=2 |pages=103–106 |bibcode=1992PDiff...7..103W |doi=10.1017/S0885715600018339 |s2cid=100926565}}

{{chem2|K2GdZr(PO4)3}}

|611.58

|10.3457

|

|random {{chem2|Gd}} and {{chem2|Zr}}

|

{{chem2|K2YHf(PO4)3}}

|630.51

|10.3075

|3.824

|

|{{cite journal |last=Ogorodnyk |first=Ivan V. |author2=Zatovsky, Igor V. |author3=Slobodyanik, Nikolay S. |year=2009 |title=Rietveld refinement of langbeinite-type K2YHf(PO4)3 |journal=Acta Crystallographica Section E |volume=65 |issue=8 |pages=i63–i64 |bibcode=2009AcCrE..65I..63O |doi=10.1107/S1600536809027573 |pmc=2977454 |pmid=21583298}}

{{chem2|Li(H2O)2Hf2(PO4)3}}

|684.87

|10.1993

|

|

|{{cite journal |last1=Chen |first1=Shuang |last2=Hoffmann |first2=Stefan |last3=Borrmann |first3=Horst |last4=Kniep |first4=Rüdiger |year=2011 |title=Crystal structure of a lithium-filled langbeinite variant, Li(H2O)2[Hf2(PO4)3] |url=http://ftp.oldenbourg.de/pub/download/frei/ncs/226-3/710067.pdf |journal=Z. Kristallogr. |volume=226 |issue=3 |pages=299–300 |doi=10.1524/ncrs.2011.0132 |s2cid=97687920 |access-date=30 June 2013 |doi-access=free}}

{{chem2|K2BiHf(PO4)3}}

|750.58

|

|

|

|{{cite journal |last1=Losilla |first1=E |date=2 September 1998 |title=NASICON to scandium wolframate transition in Li1+xMxHf2-x(PO4)3 (M=Cr, Fe): structure and ionic conductivity |journal=Solid State Ionics |volume=112 |issue=1–2 |pages=53–62 |doi=10.1016/S0167-2738(98)00207-0}}

{{chem2|Li(H2O)2Zr2(PO4)3}}

|510.33

|10.2417

|

|

|

{{chem2|K2AlSn(PO4)3}}

|508.78

|9.798

|

|

|

{{chem2|K2CrSn(PO4)3}}

|

|9.8741

|

|

|{{citation needed|date=July 2024}}

{{chem2|K2InSn(PO4)3}}

|

|10.0460

|

|

|{{citation needed|date=July 2024}}

{{chem2|K2FeSn(PO4)3}}

|

|9.921

|

|

|{{citation needed|date=July 2024}}

{{chem2|K2YbSn(PO4)3}}

|

|10.150

|

|

|{{citation needed|date=July 2024}}

{{chem2|K4Al3Ta(PO4)6}}

|988.11

|9.7262

|

|

|{{cite journal |last=Orlova |first=A. I. |author2=Koryttseva, A. K. |author3=Bortsova, E. V. |author4=Nagornova, S. V. |author5=Kazantsev, G. N. |author6=Samoilov, S. G. |author7=Bankrashkov, A. V. |author8=Kurazhkovskaya, V. S. |year=2006 |title=Crystallochemical modeling, synthesis, and study of new tantalum and niobium phosphates with a framework structure |journal=Crystallography Reports |volume=51 |issue=3 |pages=357–365 |bibcode=2006CryRp..51..357O |doi=10.1134/S1063774506030011 |s2cid=93802518}}

{{chem2|K4Cr3Ta(PO4)6}}

|1063.16

|9.8315

|

|

|

{{chem2|K4Fe3Ta(PO4)6}}

|1074.70

|9.9092

|

|

|

{{chem2|K4Tb3Ta(PO4)6}}

|

|10.3262

|

|

|{{cite journal |last1=Xue |first1=Ya-Li |last2=Zhao |first2=Dan |last3=Zhang |first3=Shi-Rui |last4=Li |first4=Ya-Nan |last5=Fan |first5=Yan-Ping |date=30 January 2019 |title=A new disordered langbeinite-type compound, K2Tb1.5Ta0.5P3O12, and Eu3+ -doped multicolour light-emitting properties |journal=Acta Crystallographica Section C |volume=75 |issue=2 |pages=213–220 |doi=10.1107/S2053229619000998 |pmid=30720461 |s2cid=73439880}}

{{chem2|K4Ga3Ta(PO4)6}}

|

|

|

|

|{{Cite journal |last1=Koryttseva |first1=A. K. |last2=Orlova |first2=A. I. |last3=Nagornova |first3=S. V. |last4=Sedova |first4=N. A. |last5=Beskrovnyi |first5=A. I. |date=April 2022 |title=Preparation and Structure of New Orthophosphates Isostructural with the Mineral Langbeinite: A2R1.5Ta0.5(PO4)3 (A = K, Rb; R = Ga, Gd, Dy, Ho, Er, Yb) |url=https://link.springer.com/10.1134/S0020168522040069 |journal=Inorganic Materials |language=en |volume=58 |issue=4 |pages=356–363 |doi=10.1134/S0020168522040069 |s2cid=249706245 |issn=0020-1685}}

{{chem2|K4Gd3Ta(PO4)6}}

|

|

|

|

|

{{chem2|K4Dy3Ta(PO4)6}}

|

|

|

|

|

{{chem2|K4Ho3Ta(PO4)6}}

|

|

|

|

|

{{chem2|K4Er3Ta(PO4)6}}

|

|

|

|

|

{{chem2|K4Yb3Ta(PO4)6}}

|

|

|

|

|

{{chem2|Rb4Ga3Ta(PO4)6}}

|

|

|

|

|

{{chem2|Rb4Gd3Ta(PO4)6}}

|

|

|

|

|

{{chem2|Rb4Dy3Ta(PO4)6}}

|

|

|

|

|

{{chem2|Rb4Ho3Ta(PO4)6}}

|

|

|

|

|

{{chem2|Rb4Er3Ta(PO4)6}}

|

|

|

|

|

{{chem2|Rb4Yb3Ta(PO4)6}}

|

|

|

|

|

{{chem2|K4Fe3Nb(PO4)6}}

|986.66

|9.9092

|

|

|

{{chem2|KBaEr2(PO4)3}}

|795.857

|

|

|

|{{cite journal |last=Orlova |first=A. I. |author2=Kitaev, D. B. |year=2005 |title=Anhydrous Lanthanide and Actinide(III) and (IV) Orthophosphates Me_m(PO4)_n. Synthesis, Crystallization, Structure, and Properties |journal=Radiochemistry |volume=47 |issue=1 |pages=14–30 |doi=10.1007/s11137-005-0041-6 |s2cid=98748508}}

{{chem2|RbBaEr2(PO4)3}}

|842.227

|

|

|

|

{{chem2|CsBaEr2(PO4)3}}

|889.665

|

|

|

|

{{chem2|(Rb,Cs)2(Pr,Er)Zr(PO4)3}}

|

|

|

|

|

{{chem2|KCsFeZrP3O12}}

|603.99

|10.103

|

|

|{{cite journal |last=Kumar |first=Sathasivam Pratheep |author2=Gopal, Buvaneswari |year=2014 |title=Synthesis and leachability study of a new cesium immobilized langbeinite phosphate: KCsFeZrP3O12 |journal=Journal of Alloys and Compounds |volume=615 |pages=419–423 |doi=10.1016/j.jallcom.2014.06.192 |issn=0925-8388}}

{{chem2|CaFe3O(PO4)3}}

|508.53

|

|

|

|{{cite journal |last=El Hafid |first=Hassan |author2=Velázquez, Matias |author3=El Jazouli, Abdelaziz |author4=Wattiaux, Alain |author5=Carlier, Dany |author6=Decourt, Rodolphe |author7=couzi, Michel |author8=Goldner, Philippe |author9=Delmas, Claude |year=2014 |title=Magnetic, Mössbauer and optical spectroscopic properties of the AFe3O(PO4)3 (A=Ca,Sr,Pb) series of powder compounds |journal=Solid State Sciences |volume=36 |pages=52–61 |bibcode=2014SSSci..36...52E |doi=10.1016/j.solidstatesciences.2014.07.011 |issn=1293-2558}}

{{chem2|SrFe3O(PO4)3}}

|556.1

|

|

|

|

{{chem2|PbFe3O(PO4)3}}

|675.6

|

|

|

|

{{chem2|KSrFe2(PO4)3}}

|523.32

|9.809

|3.68

|yellowish

|{{cite journal |last1=Hidouri |first1=Mourad |last2=López |first2=María Luisa |last3=Pico |first3=Carlos |last4=Wattiaux |first4=Alain |last5=Amara |first5=Mongi Ben |date=December 2012 |title=Synthesis and characterization of a new iron phosphate KSrFe2(PO4)3 with a langbeinite type structure |journal=Journal of Molecular Structure |volume=1030 |pages=145–148 |bibcode=2012JMoSt1030..145H |doi=10.1016/j.molstruc.2012.04.002}}

{{chem2|Pb1.5V^{IV}2(PO4)3}}

|697.6

|9.7818

|4.912

|

|{{cite journal |last=Shpanchenko |first=R. V. |author2=Lapshina, O. A. |author3=Antipov, E. V. |author4=Hadermann, J. |author5=Kaul, E. E. |author6=Geibel, C. |year=2005 |title=New lead vanadium phosphate with langbeinite-typestructure: Pb1.5V2(PO4)3 |url=https://www.academia.edu/4306164 |journal=Materials Research Bulletin |volume=40 |issue=9 |pages=1569–1576 |doi=10.1016/j.materresbull.2005.04.037}}

{{chem2|K2TiV(PO4)3}}

|

|9.855

|

|green

|{{cite journal |last1=Rangan |first1=K. Kasthuri |last2=Gopalakrishnan |first2=J. |date=March 1994 |title=New Titanium-Vanadium Phosphates of Nasicon and Langbeinite Structures, and Differences between the Two Structures toward Deintercalation of Alkali Metal |journal=Journal of Solid State Chemistry |volume=109 |issue=1 |pages=116–121 |bibcode=1994JSSCh.109..116R |doi=10.1006/jssc.1994.1080}}

{{chem2|BaTiV(PO4)3}}

|

|9.922

|3.54

|at high temperature > 950 °C dark grey

|

{{chem2|KBaV2(PO4)3}}

|

|9.873

|

|greenish yellow

|

{{chem2|Ba1.5V2(PO4)3}}

|

|9.884

|

|grey

|

{{chem2|Ba1.5Fe^{3+}2(PO4)3}}{{cite journal |last=David |first=Rénald |author2=Kabbour, Houria |author3=Filimonov, Dmitry |author4=Huvé, Marielle |author5=Pautrat, Alain |author6=Mentré, Olivier |year=2014 |title=Reversible Topochemical Exsolution of Iron in BaFe2+2(PO4)2 |journal=Angewandte Chemie |volume=126 |issue=49 |pages=13583–13588 |issn=0044-8249 |doi=10.1002/ange.201404476|bibcode=2014AngCh.12613583D }}{{cite journal |last1=Pet'kov |first1=V. I. |last2=Markin |first2=A. V. |last3=Alekseev |first3=A. A. |last4=Smirnova |first4=N. N. |title=Heat capacity measurements on Ba1.5Fe2(PO4)3 and its thermodynamic functions |journal=Journal of Thermal Analysis and Calorimetry |volume=132 |pages=353–364 |date=3 February 2018 |doi=10.1007/s10973-017-6925-9 |s2cid=103383453}}

|602.59

|

|

|

|

{{chem2|KSrSc2(PO4)3}}{{cite journal |last1=Jiao |first1=Mengmeng |last2=Lv |first2=Wenzhen |last3=Lv |first3=Wei |last4=Zhao |first4=Qi |last5=Shao |first5=Baiqi |last6=You |first6=Hongpeng |title=Optical Properties and Energy Transfer of Novel KSrSc2(PO4)3:Ce3+/Eu2+/Tb3+ Phosphor for White Light Emitting Diodes |journal=Dalton Trans. |date=14 January 2015 |doi=10.1039/C4DT03906H |pmid=25623365 |volume=44 |issue=9 |pages=4080–4087}}

|501.54

|

|

|

|

{{chem2|Rb0.743K0.845Co0.293Ti1.707(PO4)3}}{{cite journal |last1=Strutynska |first1=Nataliia Yu. |last2=Bondarenko |first2=Marina A. |last3=Ogorodnyk |first3=Ivan V. |last4=Baumer |first4=Vyacheslav N. |last5=Slobodyanik |first5=Nikolay S. |title=Crystal structure of langbeinite-related RbKCoTi(PO4)3 |journal=Acta Crystallographica Section E |date=7 February 2015 |volume=71 |issue=3 |pages=251–253 |doi=10.1107/S2056989015001826 |pmid=25844179 |pmc=4350725}}

|

|9.8527

|

|

|

{{chem2|K2BiZr(PO4)6}}{{cite journal |last1=Chornii |first1=Vitalii |last2=Hizhnyi |first2=Yuriy |last3=Nedilko |first3=Sergiy G. |last4=Terebilenko |first4=Kateryna |last5=Zatovsky |first5=I. |last6=Ogorodnyk |first6=Ivan |last7=Boyko |first7=Volodymyr |title=Synthesis, Crystal Structure, Luminescence and Electronic Band Structure of K2BiZr(PO4)3 Phosphate Compound |journal=Solid State Phenomena |date=June 2015 |volume=230 |pages=55–61 |doi=10.4028/www.scientific.net/SSP.230.55 |s2cid=101559407 }}

|663.32

|10.3036

|

|

|

{{chem2|KBaSc2(PO4)3}}{{cite journal |last1=Jiao |first1=Mengmeng |last2=Lü |first2=Wei |last3=Shao |first3=Baiqi |last4=Zhao |first4=Lingfei |last5=You |first5=Hongpeng |title=Synthesis, Structure, and Photoluminescence Properties of Novel KBaSc2(PO4)3 :Ce/Eu/Tb Phosphors for White-Light-Emitting Diodes |journal=ChemPhysChem |date=20 July 2015 |doi=10.1002/cphc.201500387 |pmid=26202348 |volume=16 |issue=12 |pages=2663–2669}}

|503.25

|

|

|

|

{{chem2|KBaIn2(PO4)3}}{{cite journal |last1=Wu |first1=Di |last2=Si |first2=Jiayong |last3=Tang |first3=Jiamin |last4=Li |first4=Guihua |last5=Cai |first5=Gemei |title=Structure and tunable luminescence of Tm3+/Dy3+ doped KBaIn2(PO4)3 phosphors with high thermal stability |journal=Journal of Luminescence |date=September 2022 |volume=252 |pages=119291 |doi=10.1016/j.jlumin.2022.119291|bibcode=2022JLum..252k9291W |s2cid=252195013 }}

|

|

|

|

|

{{chem2|KBaRZrP2SiO12}}{{cite journal |last1=Kumar |first1=Sathasivam Pratheep |last2=Gopal |first2=Buvaneswari |title=New rare earth langbeinite phosphosilicates KBaREEZrP2SiO12 (REE: La, Nd, Sm, Eu, Gd, Dy) for lanthanide comprising nuclear waste storage |journal=Journal of Alloys and Compounds |date=October 2015 |doi=10.1016/j.jallcom.2015.10.088 |volume=657 |pages=422–429}}

|

|

|

| R = La, Nd, Sm, Eu, Gd, Dy, Y

|

{{chem2|KBaYSnP2SiO12}}

|666.07

|

|

|

|

{{chem2|KBaFe2(PO4)3}}{{cite journal |last1=Battle |first1=Peter D. |last2=Cheetham |first2=Anthony K. |last3=Harrison |first3=William T. A. |last4=Long |first4=Gary J. |title=The crystal structure and magnetic properties of the synthetic langbeinite KBaFe2(PO4)3 |journal=Journal of Solid State Chemistry |date=March 1986 |volume=62 |issue=1 |pages=16–25 |doi=10.1016/0022-4596(86)90211-2 |bibcode= 1986JSSCh..62...16B }}

|525.03

|9.8732 (at 4 K)

|

|

|

{{chem2|KBaCr2(PO4)3}}{{cite journal |last1=Battle |first1=P. D. |last2=Gibb |first2=T. C. |last3=Nixon |first3=S. |last4=Harrison |first4=W. T. A. |title=The magnetic properties of the synthetic langbeinite KBaCr2(PO4)3 |journal=Journal of Solid State Chemistry |date=July 1988 |volume=75 |issue=1 |pages=21–29 |doi=10.1016/0022-4596(88)90299-x |bibcode=1988JSSCh..75...21B }}

|517.33

|9.7890

|

|

|

{{chem2|Rb2FeTi(PO4)3}}{{cite journal |last1=Pet'kov |first1=V. I. |last2=Asabina |first2=E. A. |last3=Markin |first3=A. V. |last4=Alekseev |first4=A. A. |last5=Smirnova |first5=N. N. |title=Thermodynamic investigation of Rb2FeTi(PO4)3 phosphate of langbeinite structure |journal=Journal of Thermal Analysis and Calorimetry |date=22 February 2016 |doi=10.1007/s10973-016-5319-8 |volume=124 |issue=3 |pages=1535–1544 |s2cid=100260297}}

|511.56

|9.8892

|

|{{chem2|Na2FeTi(PO4)3}} has NZP structure

|

{{chem2|KBaMgTi(PO4)3}}{{cite journal |last1=Pet'kov |first1=V. I. |last2=Alekseev |first2=A. A. |last3=Asabina |first3=E. A. |last4=Borovikova |first4=E. Yu. |last5=Koval'skii |first5=A. M. |title=Synthesis, structure formation, and thermal expansion of A+M2+MgE4+(PO4)3 |journal=Russian Journal of Inorganic Chemistry |date=6 August 2017 |volume=62 |issue=7 |pages=870–878 |doi=10.1134/S0036023617070178 |s2cid=103520759}}

|485.51

|9.914

|

|{{chem2|KSrMgTi}} crystallises in kosnarite form

|

{{chem2|KPbMgTi(PO4)3}}

|555.39

|9.8540

|

|{{chem2|KSrMgTi}} in kosnarite form

|

{{chem2|RbBaMgTi(PO4)3}}

|

|9.954

|531.88

|{{chem2|CsBa}} does not form

|

{{chem2|RbPbMgTi(PO4)3}}

|601.76

|9.9090

|

|{{chem2|CsPb}} does not form

|

{{chem2|KSrMgZr(PO4)3}}

|479.16

|10.165

|

|

|

{{chem2|KPbMgZr(PO4)3}}

|598.74

|10.111

|

|

|

{{chem2|KBaMgZr(PO4)3}}

|528.87

|10.106

|

|

|

{{chem2|RbSrMgZr(PO4)3}}

|525.53

|10.218

|

|

|

{{chem2|RbPbMgZr(PO4)3}}

|645.11

|10.178

|

|

|

{{chem2|RbBaMgZr(PO4)3}}

|575.24

|10.178

|

|

|

{{chem2|CsSrMgZr(PO4)3}}

|572.97

|10.561

|

|over 1250 °C forms kosnarite phase

|

{{chem2|Ba3In4(PO4)6}}

|

|10.1129

|

|

|{{cite journal |last1=Zhang |first1=G.X. |last2=Zhang |first2=J. |last3=Liu |first3=Y.J. |last4=Si |first4=J.Y. |last5=Tao |first5=X.M. |last6=Cai |first6=G.M. |date=May 2019 |title=Structure and luminescence properties of multicolor phosphors with excellent thermal stability based on a new phosphate Ba3In4(PO4)6 |journal=Journal of Alloys and Compounds |volume=797 |pages=775–785 |doi=10.1016/j.jallcom.2019.05.059 |s2cid=182926209}}

{{chem2|Ba3V4(PO4)6}}

|1185.58

|9.8825

|4.08

|yellow-green

|{{cite journal |last1=Droß |first1=Thomas |last2=Glaum |first2=Robert |date=20 March 2004 |title=The langbeinite-type barium vanadium(III) orthophosphate, Ba3V4(PO4) 6 |journal=Acta Crystallographica Section E |volume=60 |issue=4 |pages=i58–i60 |bibcode=2004AcCrE..60I..58D |doi=10.1107/S1600536804005689 |s2cid=61648994}}

{{chem2|KPbCr2(PO4)3}}

|

|9.7332

|

|

|{{cite journal |last1=Balaji |first1=Daneshwaran |last2=Mandlimath |first2=Triveni Rajashekhar |last3=Chen |first3=Jie |last4=Matsushita |first4=Yoshitaka |last5=Kumar |first5=Sathasivam Pratheep |date=2020-09-02 |title=Langbeinite Phosphates KPbM2(PO4)3 (M = Cr, Fe): Synthesis, Structure, Thermal Expansion, and Magnetic Properties Investigation |journal=Inorganic Chemistry |language=en |volume=59 |issue=18 |pages=13245–13253 |doi=10.1021/acs.inorgchem.0c01597 |issn=0020-1669 |pmid=32878438 |s2cid=221478204}}

{{chem2|KPbFe2(PO4)3}}

|

|9.8325

|

|beige

|

{{chem2|K4NiHf3(PO4)6}}

|660.192 (half)

|10.12201

|4.228

|yellow

|{{cite journal |last1=Zhou |first1=Liang |last2=Butenko |first2=Denys S. |last3=Ogorodnyk |first3=Ivan V. |last4=Klyui |first4=Nickolai I. |last5=Zatovsky |first5=Igor V. |date=2020-10-01 |title=Rietveld refinement of the langbeinite-type phosphate K2Ni0.5Hf1.5(PO4)3 |url=http://scripts.iucr.org/cgi-bin/paper?S2056989020012062 |journal=Acta Crystallographica Section E |volume=76 |issue=10 |pages=1634–1637 |bibcode=2020AcCrE..76.1634Z |doi=10.1107/S2056989020012062 |issn=2056-9890 |pmc=7534254 |pmid=33117578}}

{{chem2|NaBaBi2(PO3)3}}

|

|

|

|

|{{cite journal |last1=Indumathi |first1=K. |last2=Tamilselvan |first2=S. |last3=Annadurai |first3=G. |last4=Ramalingam |first4=Gopal |last5=Muhammad |first5=G. Shakil |last6=Alam |first6=Mohammed Mujahid |last7=David |first7=A. Duke John |last8=Ayyar |first8=Manikandan |date=January 2024 |title=Photoluminescence and structural properties of NaBaBi2[PO4]3 an Eulytite-type orthophosphate doped with Sm3+ as new orange-red emitting phosphors |journal=Journal of Materials Science: Materials in Electronics |volume=35 |issue=2 |doi=10.1007/s10854-024-11936-7|s2cid=267054200 }}

Phosphate silicates

class="wikitable"

!substance

!formula weight

!unit cell edge Å

!density

!comment

!ref

K2Sn2(PO4)2SiO4{{cite journal |last1=Balaji |first1=Daneshwaran |last2=Mandlimath |first2=Triveni Rajashekhar |last3=Kumar |first3=Sathasivam Pratheep |title=Influence of tin substitution on negative thermal expansion of K2Zr2-xSnxP2SiO12 (x = 0 - 2) phosphosilicates ceramics |journal=Ceramics International |date=February 2020 |volume=46 |issue=9 |pages=13877–13885 |doi=10.1016/j.ceramint.2020.02.181|s2cid=213437625 }}

|

|

|

|Stable to 650 °C

|

K2Zr2(PO4)2SiO4

|

|

|

|Stable to 1000 °C

|

Cs2Zr2(PO4)2SiO4{{Cite journal|last1=Balaji|first1=Daneshwaran|last2=Kumar|first2=Sathasivam Pratheep|date=July 2021|title=Langbeinite phosphosilicates K2-xCsxZr2P2SiO12 (x = 0, 0.5, 1.0, 1.5, 2.0) for cesium encapsulation; synthesis, chemical durability and thermal expansion study|url=https://linkinghub.elsevier.com/retrieve/pii/S0272884221020824|journal=Ceramics International|volume=47|issue=20|language=en|pages=28951–28959|doi=10.1016/j.ceramint.2021.07.055}}

|

|

|

|

|

CsKZr2(PO4)2SiO4

|

|

|

|

|

KBaZrY(PO4)2SiO4

|

|

|

|

|{{Cite journal |last1=Kumar |first1=Sathasivam Pratheep |last2=Gopal |first2=Buvaneswari |date=February 2016 |title=New rare earth langbeinite phosphosilicates KBaREEZrP 2 SiO 12 (REE: La, Nd, Sm, Eu, Gd, Dy) for lanthanide comprising nuclear waste storage |url=https://linkinghub.elsevier.com/retrieve/pii/S092583881531344X |journal=Journal of Alloys and Compounds |language=en |volume=657 |pages=422–429 |doi=10.1016/j.jallcom.2015.10.088}}

KBaZrLa(PO4)2SiO4

|

|

|

|

|

KBaZrNd(PO4)2SiO4

|

|

|

|

|

KBaZrSm(PO4)2SiO4

|

|

|

|

|

KBaZrEu(PO4)2SiO4

|

|

|

|

|

Mixed anion phosphates

class="wikitable"

!substance

!formula weight

!unit cell edge Å

!density

!comment

!ref

K2MgTi(SO4)(PO4)2

|

|

|

|

|{{Cite journal |last1=Kanunov |first1=A. E. |last2=Asabina |first2=E. A. |last3=Orlova |first3=A. I. |date=January 2016 |title=Preparation and X-ray diffraction study of phosphate sulfates M2MgTi(SO4)(PO4)2 |url=http://link.springer.com/10.1134/S1070363216010047 |journal=Russian Journal of General Chemistry |language=en |volume=86 |issue=1 |pages=18–25 |doi=10.1134/S1070363216010047 |s2cid=102011872 |issn=1070-3632}}

K2Fe2(MoO4)(PO4)2

|

|

|

|

|{{Cite journal |last1=Slobodyanik |first1=Nikolay S. |last2=Terebilenko |first2=Kateryna V. |last3=Ogorodnyk |first3=Ivan V. |last4=Zatovsky |first4=Igor V. |last5=Seredyuk |first5=Maksym |last6=Baumer |first6=Vyacheslav N. |last7=Gütlich |first7=Philipp |date=2012-02-06 |title=K 2 M III 2 (M VI O 4 )(PO 4 ) 2 (M III = Fe, Sc; M VI = Mo, W), Novel Members of the Lagbeinite-Related Family: Synthesis, Structure, and Magnetic Properties |url=https://pubs.acs.org/doi/10.1021/ic201575v |journal=Inorganic Chemistry |language=en |volume=51 |issue=3 |pages=1380–1385 |doi=10.1021/ic201575v |pmid=22260084 |issn=0020-1669}}

K2Sc2(MoO4)(PO4)2

|

|

|

|

|

K2Sc2(WO4)(PO4)2

|

|

|

|

|

Vanadates

The orthovanadates have four formula per cell, with a slightly distorted cell that has orthorhombic symmetry.

class="wikitable"

|

|formula weight

|comment

|colspan=3|Cell dimensions Å

|Volume

|density

|refractive

Formula

|g/mol

|symmetries

|a

|b

|c

|

|

|index

{{chem2|LiBaCr2(VO4)3}}{{cite journal |last1=Nabar |first1=M. A. |last2=Phanasgaonkar |first2=D. S. |title=Preparation and X-ray powder diffraction studies of triple orthovanadates having langbeinite structure |journal=Journal of Applied Crystallography |date=1 October 1980 |volume=13 |issue=5 |pages=450–451 |doi=10.1107/s0021889880012514|doi-access=free |bibcode=1980JApCr..13..450N }}

|593.08

|Orthorhombic

|9.98

|10.52

|9.51

|998

|4.02

{{chem2|NaBaCr2(VO4)3}}

|609.13

|Orthorhombic

|9.99

|10.52

|9.53

|1002

|4.09

{{chem2|AgBaCr2(VO4)3}}

|694.00

|Orthorhombic

|10.02

|10.53

|9.53

|1005

|4.62

Arsenates

class="wikitable"

!substance

!formula weight

!unit cell edge Å

!density

{{chem2|K2ScSn(AsO4)3}}{{cite journal |last1=Harrison |first1=William T. A. |title=K2ScSn(AsO4)3 : an arsenate-containing langbeinite |journal=Acta Crystallographica Section C |date=17 June 2010 |volume=66 |issue=7 |pages=i82–i84 |doi=10.1107/S0108270110021670 |pmid=20603547 |bibcode=2010AcCrC..66I..82H |url=http://repositorio.unicamp.br/jspui/handle/REPOSIP/198934}}

|658.62

|10.3927

|

{{chem2|Zr2NH4(AsO4)3*H2O}}{{cite book |last1=Rouse |first1=Jessica |title=Synthesis and Characterisation of Lanthanide and Other Inorganic Framework Materials |url=http://eprints.soton.ac.uk/173801/1.hasCoversheetVersion/FINAL_AH_CHECK.pdf |publisher=University of Southampton, Faculty of Engineering, Science and Mathematics, School of Chemistry |access-date=10 November 2015 |page=127 |format=Thesis |date=January 2010 |chapter=Compound IX:hydrated ammonium zirconium arsenate}}

|632.558

|10.532

|3.379

Selenates

Langbeinite structured double selenates are difficult to make, perhaps because selenate ions arranged around the dication leave space for water, so hydrates crystallise from double selenate solutions. For example, when ammonia selenate and cadmium selenate solution is crystallized it forms diammonium dicadmium selenate trihydrate: {{chem2|(NH4)2Cd2(SeO4)3*3H2O}} and when heated it loses both water and ammonia to form a pyroselenate rather than a langbeinite.{{cite journal |last1=Martínez |first1=M. L. |last2=Rodriguez |first2=A. |last3=Mestres |first3=L. |last4=Solans |first4=X. |last5=Bocanegra |first5=E. H. |title=Synthesis, crystal structure, and thermal studies of (NH4)2Cd2(SeO4)3·3H2O |journal=Journal of Solid State Chemistry |date=November 1990 |volume=89 |issue=1 |pages=88–93 |doi=10.1016/0022-4596(90)90297-B |bibcode=1990JSSCh..89...88M}}

class="wikitable"

!substance

!formula weight

!unit cell edge Å

!density

!note

{{chem2|(NH4)2Mn2(SeO4)3}}{{cite journal |last1=Kohler |first1=K. |last2=Franke |first2=W. |title=(NH4)2Mn2(SeO4)3, Ein Doppelselenat mit Langbeiniestruktur |journal=Acta Crystallographica |date=1 August 1964 |volume=17 |issue=8 |pages=1088–1089 |doi=10.1107/s0365110x64002833 |language=de|doi-access=free |bibcode=1964AcCry..17.1088K }}

|574.83

|10.53

|3.26

|forms continuous series with {{chem2|SO4}} too

Molybdates

class="wikitable"

!substance

!formula weight

!unit cell edge Å

!density

!ref

{{chem2|Cs2Cd2(MoO4)3}}

|970.5

|11.239

|

|{{cite journal |last=Tsyrenova |first=G. D. |author2=N. N. Pavlova |year=2011 |title=Synthesis, structure, and electrical and acoustic properties of Cs2Cd2(MoO4)3 |journal=Inorganic Materials |volume=47 |issue=7 |pages=786–790 |doi=10.1134/S0020168511070235 |s2cid=97308112}}

{{chem2|Rb2Co2(MoO4)3}}

|768.7

|

|

|

{{chem2|Cs2Co2(MoO4)3}}

|

|

|

|{{cite journal |last1=Yudin |first1=Vasiliy N. |last2=Zolotova |first2=Evgeniya S. |last3=Solodovnikov |first3=Sergey F. |last4=Solodovnikova |first4=Zoya A. |last5=Korolkov |first5=Iliya V. |last6=Stefanovich |first6=Sergey Yu. |last7=Kuchumov |first7=Boris M. |date=23 November 2018 |title=Synthesis, structure and conductivity of alluaudite-related phases in the Na2MoO4-Cs2MoO4-CoMoO4 system |journal=European Journal of Inorganic Chemistry |volume=2019 |issue=2 |pages=277–286 |doi=10.1002/ejic.201801307 |s2cid=105126213}}

Cs2Fe2(MoO4)3

|

|10.9112

|

|{{Cite journal |last=Kubíčková |first=Lenka |last2=Weber |first2=Anna Katharina |last3=Panthöfer |first3=Martin |last4=Calder |first4=Stuart |last5=Möller |first5=Angela |date=2024-07-02 |title=Cs 2 Fe 2 (MoO 4 ) 3 ─A Strongly Frustrated Magnet with Orbital Degrees of Freedom and Magnetocaloric Properties |url=https://pubs.acs.org/doi/10.1021/acs.chemmater.4c01262 |journal=Chemistry of Materials |language=en |doi=10.1021/acs.chemmater.4c01262 |issn=0897-4756|doi-access=free |pmc=11270738 }}

{{chem2|Cs2Ni2(MoO4)3}}

|863.01

|10.7538

|

|{{cite journal |last1=Zolotova |first1=E. S. |last2=Solodovnikova |first2=Z. A. |last3=Ayupov |first3=B. M. |last4=Solodovnikov |first4=S. F. |date=16 August 2011 |title=Phase formation in the Li2MoO4-A2MoO4-NiMoO4 (A = K, Rb, Cs) systems, the crystal structure of Cs2Ni2(MoO4)3, and color characteristics of alkali-metal nickel molybdates |journal=Russian Journal of Inorganic Chemistry |volume=56 |issue=8 |pages=1216–1221 |doi=10.1134/S0036023611080298 |s2cid=96079887}}

{{chem2|(H3O)2Mn2(MoO4)3}}

|627.75

|10.8713

|

|{{cite journal |last1=Yu |first1=Yang |last2=Liu |first2=Dan |last3=Hu |first3=Wei-wei |last4=Li |first4=Jia |last5=Peng |first5=Yu |last6=Zhou |first6=Qi |last7=Yang |first7=Fen |last8=Li |first8=Guang-hua |last9=Shi |first9=Zhan |date=2012 |title=Synthesis, Structure and Characterization of Three Metal Molybdate Hydrates: Fe(H2O)2(MoO4)2·H3O, NaCo2(MoO4)2(H3O2) and Mn2(MoO4)3·2H3O |url=http://www.cjcu.jlu.edu.cn/hxyj/EN/article/downloadArticleFile.do?attachType=PDF&id=15425 |journal=Chem Res. Chinese Universities |volume=28 |issue=2 |pages=186–190 |access-date=10 November 2015}}

{{chem2|K2Mn2(MoO4)3}}

|

|

|

|{{cite journal |last1=Gulyaeva |first1=Oksana A. |last2=Solodovnikova |first2=Zoya A. |last3=Solodovnikov |first3=Sergey F. |last4=Yudin |first4=Vasiliy N. |last5=Zolotova |first5=Evgeniya S. |last6=Komarov |first6=Vladislav Yu. |date=April 2019 |title=Subsolidus phase relations and structures of solid solutions in the systems K2MoO4–Na2MoO4–MMoO4 (M = Mn, Zn) |journal=Journal of Solid State Chemistry |volume=272 |pages=148–156 |bibcode=2019JSSCh.272..148G |doi=10.1016/j.jssc.2019.02.010 |s2cid=104469445}}

Tungstates

class="wikitable"

!substance

!formula weight

!unit cell edge Å

!density

{{chem2|Rb2Mg2(WO4)3}}{{cite journal |last1=Han |first1=Shujuan |last2=Wang |first2=Ying |last3=Jing |first3=Qun |last4=Wu |first4=Hongping |last5=Pan |first5=Shilie |last6=Yang |first6=Zhihua |title=Effect of the cation size on the framework structures of magnesium tungstate, A4Mg(WO4)3 (A = Na, K), R2Mg2 (WO4)3 (R = Rb, Cs) |journal=Dalton Trans. |date=2015 |volume=44 |issue=12 |pages=5810–5817 |doi=10.1039/c5dt00332f |pmid=25715112}}

|963.06

|10.766

|

{{chem2|Cs2Mg2(WO4)3}}

|1057.93

|10.878

|

Preparation

Diammonium dicadmium sulfate can be made by evaporating a solution of ammonium sulfate and cadmium sulfate. Dithallium dicadmium sulfate can be made by evaporating a water solution at 85 °C. Other substances may be formed during crystallisation from water such as Tutton's salts or competing compounds like {{chem2|Rb2Cd3(SO4)4*5H2O}}.{{cite journal |last=Swain |first=Diptikanta |author2=T. N. Guru Row |year=2005 |title=Dirubidium tricadmium tetrakis(sulfate) pentahydrate |journal=Acta Crystallographica Section E |volume=61 |issue=8 |pages=i163–i164|doi=10.1107/S1600536805021252 |bibcode=2005AcCrE..61I.163S |url=http://eprints.iisc.ernet.in/3645/1/A156.pdf}}

Potassium and ammonium nickel langbeinite can be made from nickel sulfate and the other sulfates by evaporating a water solution at 85 °C.

Dipotassium dizinc sulfate can be formed into large crystals by melting zinc sulfate and potassium sulfate together at 753 K. A crystal can be slowly drawn out of the melt from a rotating crucible at about 1.2 mm every hour.{{cite journal |last=Yamada |first=N. |author2=Tomoyuki Hikita |author3=Kazuhiro Yamada |year=1981 |title=Pyroelectric properties of langbeinite-type K2Zn2(SO4)3 |journal=Ferroelectrics |volume=33 |issue=1 |pages=59–61 |doi=10.1080/00150198108008070|bibcode=1981Fer....33...59Y }}

{{chem2|Li(H2O)2Hf2(PO4)3}} can be made by heating {{chem2|HfCl4}}, {{chem2|Li2B4O7}}, {{chem2|H3PO4}}, water and hydrochloric acid to 180 °C for eight days under pressure.

{{chem2|Li(H2O)2Hf2(PO4)3}} converts to {{chem2|Li2Hf2(PO4)3}} on heating to 200 °C.

The sol-gel method produces a gel from a solution mixture, which is then heated. {{chem2|Rb2FeZr(PO4)3}} can be made by mixing solutions of {{chem2|FeCl3}}, {{chem2|RbCl}}, {{chem2|ZrOCl2}}, and dripping in {{chem2|H3PO4}}. The gel produced was dried out at 95 °C and then baked at various temperatures from 400 to 1100 °C.

Langbeinites crystals can be made by the Bridgman technique, Czochralski process or flux technique.

A Tutton's salt may be heat treated and dehydrate, e.g. {{chem2|(NH4)2Mn2(SeO4)3}} can be made from {{chem2|(NH4)2Mn(SeO4)3*6(H2O)}} heated to 100 °C, forming {{chem2|(NH4)2(SeO4)}} as a side product.{{cite journal |last=Kohler |first=K. |author2=W. Franke |year=1964 |title=(NH4)2Mn2(SeO4)3, Ein Doppelselenat mit Langbeiniestruktur |journal=Acta Crystallographica |volume=17 |issue=8 |pages=1088–1089 |doi=10.1107/S0365110X64002833|doi-access=free |bibcode=1964AcCry..17.1088K }} Similarly the ammonium vanadium Tutton's salt, {{chem2|(NH4)2V(SO4)2}}, heated to 160 °C in a closed tube produces {{chem2|(NH4)2V2(SO4)3}}. At lower temperatures a hydroxy compound is formed.

Use

Few uses have been made of these substances. Langbeinite itself can be used as an "organic" fertiliser with potassium, magnesium and sulfur, all needed for plant growth. Electrooptic devices could be made from some of these crystals, particularly those that have cubic transition temperatures as temperatures above room temperature. Research continues into this. Ferroelectric crystals could store information in the location of domain walls.

The phosphate langbeinites are insoluble, stable against heat, and can accommodate a large number of different ions, and have been considered for immobilizing unwanted radioactive waste.{{cite journal |last=Orlova |first=A. I. |author2=V. A. Orlova |author3=M. P. Orlova |author4=D. M. Bykov |author5=S. V. Stefanovskii |author6=O. I. Stefanovskaya |author7=B. S. Nikonov |year=2006 |title=The crystal-chemical principle in designing mineral-like phosphate ceramics for immobilization of radioactive waste |journal=Radiochemistry |volume=48 |issue=4 |pages=330–339 |doi=10.1134/S1066362206040035 |s2cid=97539628}}

Zirconium phosphate langbeinites containing rare earth metals have been investigated for use in white LEDs and plasma displays. Langbeinites that contain bismuth are photoluminescent.

In case of iron-containing ones complex magnetic behavior may be found.{{cite journal |last=Slobodyanik |first=M. S. |author2=N. S. Slobodyanik |author3=K. V. Terebilenko |author4=I. V. Ogorodnyk |author5=I. V. Zatovsky |author6=M. Seredyuk |author7=V. N. Baumer |author8=P. Gütlich |year=2012 |title=K2MIII2(MVIO4)(PO4)2 (MIII = Fe, Sc; MVI = Mo, W), Novel Members of the Lagbeinite-Related Family: Synthesis, Structure, and Magnetic Properties |journal=Inorg. Chem. |volume=51 |issue=5 |pages=1380–1385 |doi=10.1021/ic201575v |pmid=22260084}}

References

{{Reflist|30em}}

Category:Crystals

Category:Ferroelectric materials

*

Category:Crystal structure types