Thulium(III) oxide
{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 428987369
| Name = Thulium(III) oxide
| ImageFile = Tl2O3structure.jpg
| ImageName = Thulium(III) oxide
| OtherNames = Thulium oxide, thulium sesquioxide
| IUPACName = Thulium(III) oxide
| Section1 = {{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 12036-44-1
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = DZJ5EE05EB
| EC_number = 234-851-6
| PubChem = 159411
| InChI = 1S/3O.2Tm/q3*-2;2*+3
| SMILES = [O-2].[O-2].[O-2].[Tm+3].[Tm+3]
}}
| Section2 = {{Chembox Properties
| Formula = Tm2O3
| MolarMass = 385.866 g/mol
| Appearance = greenish-white cubic crystals
| Density = 8.6 g/cm3
| Solubility =
| SolubleOther = Slightly soluble in acids
| MeltingPtC = 2341
| BoilingPtC = 3945
| MagSus = +51,444·10−6 cm3/mol
}}
| Section3 = {{Chembox Structure
}}
| Section4 = {{Chembox Thermochemistry
| Thermochemistry_ref =
| HeatCapacity = 2.515 °Cp (25 °C)
}}
| Section7 = {{Chembox Hazards
| ExternalSDS = [https://www.sigmaaldrich.com/US/en/sds/aldrich/289167?userType=anonymous Sigma-Aldrich]
| GHSPictograms = {{GHS07}}
}}
| Section9 = {{Chembox Related
| OtherAnions = Thulium(III) chloride
| OtherCations = Erbium(III) oxide
Ytterbium(III) oxide
}}
}}
Thulium(III) oxide is a pale green crystalline compound, with the formula Tm2O3. It was first isolated in 1879, from an impure sample of erbia, by Swedish chemist Per Teodor Cleve, who named it thulia.
Synthesis
Thulium(III) oxide has been made in the laboratory using various methods. One method involves burning thulium metal or its various salts in air.{{cite book |author1=Catherine E. Housecroft |title=Inorganic Chemistry, 3rd Edition |author2=Alan G. Sharpe |publisher=Pearson |year=2008 |isbn=978-0-13-175553-6 |page=864 |chapter=Chapter 25: The f-block metals: lanthanoids and actinoids}}{{Cite journal |last1=Justice |first1=Bruce |last2=Westrum |first2=Edgar |last3=Chang |first3=Elfreda |last4=Radebaugh |first4=Ray |date=February 1, 1969 |title=Thermophysical properties of the lanthanide oxides. IV. Heat capacities and thermodynamic properties of thulium(III) and lutetium(III) oxides. Electronic energy levels of several lanthanide(III) ions |url=https://pubs.acs.org/doi/10.1021/j100722a010 |journal=Journal of Physical Chemistry |volume=2 |issue=73 |pages=333–340 |doi=10.1021/j100722a010 |via=ACSPublications}}
Thulium(III) oxide can be made using a hydrothermal method where thulium(III) acetate is mixed with an ammonia solution, which causes thulium(III) oxide to precipitate as a white solid.{{Cite journal |last1=Lee |first1=Sung Woo |last2=Park |first2=Seong Kyun |last3=Min |first3=Bong-Ki |last4=Kang |first4=Jun-Gill |last5=Sohn |first5=Youngku |date=July 2014 |title=Structural/spectroscopic analyses and H2/O2/CO responses of thulium(III) oxide nanosquare sheets |url=https://linkinghub.elsevier.com/retrieve/pii/S0169433214009234 |journal=Applied Surface Science |language=en |volume=307 |pages=736–743 |doi=10.1016/j.apsusc.2014.04.149}}
Properties
Thulium(III) oxide (Tm₂O₃) is a pale green, thermally stable powder with a high melting point of 2,341 °C and a density of 8.6 g/cm³, typically forming a cubic crystal structure.{{cite web |url=https://www.stanfordmaterials.com/blog/thulium-oxide-properties-and-applications.html |title=Thulium Oxide: Properties and Applications of This Rare Earth Compound |last=Loewen |first=Eric |website=Standford Advanced Materials |access-date=Oct 30, 2024}} It is resistant to oxidation and dissolves in strong acids like hydrochloric acid, allowing it to form soluble thulium salts.{{cite journal |last1=Mitrovic |first1=I.Z. |last2=Hall |first2=S |year=2015 |title=Atomic-layer deposited thulium oxide as a passivation layer on germanium |journal=Journal of Applied Physics |volume=117 |issue=21 |page=21404 |doi=10.1063/1.4922121
|url=https://hal.archives-ouvertes.fr/hal-01720449/file/1.4922121.pdf }} Due to its unique f-electron configuration, Tm₂O₃ has notable optical properties.{{cite journal |last1=Chaneliere |first1=T |last2=Ruggiero |first2=J |year=2008 |title=Tm3+:Y2O3 investigated for a quantum light storage application |journal= Physical Review B|volume=77 |issue=24 |page=245127 |doi=10.1103/PhysRevB.77.245127}} Thulium oxide (Tm₂O₃) is considered fibrogenic; it has the potential to induce tissue injury and fibrosis when inhaled or otherwise introduced to biological tissue.{{cite web |url=https://pubchem.ncbi.nlm.nih.gov/compound/Thulium-oxide |title=PubChem Compound Summary for CID 159411, Thulium oxide |year=2024 |website=National Center for Biotechnology Information |access-date=Oct 30, 2024}}