Lutetium phthalocyanine
{{Chembox
| ImageFileL1 = Lutetium bis-phthalocyanine.svg
| ImageSizeL1 = 150
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| ImageFileR1 = LuPc2.svg
| ImageSizeR1 = 150
| ImageFileL2 = Lutetium-phthalocyanine-from-xtal-view-2-3D-bs-17-25.png
| ImageSizeL2 = 150
| ImageFileR2 = Lutetium-phthalocyanine-from-xtal-view-1-3D-bs-17-25.png
| ImageSizeR2 = 150
| IUPACName =
| OtherNames = Lutetium bisphthalocyanine
Lutetium biphthalocyanine
| Section1 = {{Chembox Identifiers
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| SMILES = C15=CC=CC=C1C6=NC9=C2C=CC=CC2=C(N=C4C3=CC=CC=C3C(=N4)N=C7C8=C(C(=NC5=N6)[N-]7)C=CC=C8)[N-]9.C%10%14=CC=CC=C%10C%15=NC%18=C%11C=CC=CC%11=C(N=C%13C%12=CC=CC=C%12C(=N%13)N=C%16C%17=C(C(=NC%14=N%15)[N-]%16)C=CC=C%17)[N-]%18.[Lu+3]
| StdInChI=1S/2C32H16N8.Lu/c2*1-2-10-18-17(9-1)25-33-26(18)38-28-21-13-5-6-14-22(21)30(35-28)40-32-24-16-8-7-15-23(24)31(36-32)39-29-20-12-4-3-11-19(20)27(34-29)37-25;/h2*1-16H;/q2*-2;+3
StdInChIKey=YBUYPYVECVICRC-UHFFFAOYSA-N
}}
| Section2 = {{Chembox Properties
| Formula = {{chem2|LuC64H32N16}}
| MolarMass = 1200.04 g/mol
| Appearance = green solid; red when oxidized; blue when reduced
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| Section3 = {{Chembox Hazards
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Lutetium phthalocyanine ({{chem2|LuPc2}}) is a coordination compound derived from lutetium and two phthalocyanines. It was the first known example of a molecule that is an intrinsic semiconductor.{{cite journal |last1=Belarbi |first1=Z. |last2=Sirlin |first2=C. |last3=Simon |first3=J. |last4=Andre |first4=Jean Jacques |title=Electrical and magnetic properties of liquid crystalline molecular materials: lithium and lutetium phthalocyanine derivatives |journal=The Journal of Physical Chemistry |date=November 1989 |volume=93 |issue=24 |pages=8105–8110 |doi=10.1021/j100361a026}}{{cite journal |last1=Trometer |first1=M. |last2=Even |first2=R. |last3=Simon |first3=J. |last4=Dubon |first4=A. |last5=Laval |first5=J.-Y. |last6=Germain |first6=J.P. |last7=Maleysson |first7=C. |last8=Pauly |first8=A. |last9=Robert |first9=H. |title=Lutetium bisphthalocyanine thin films for gas detection |journal=Sensors and Actuators B: Chemical |date=May 1992 |volume=8 |issue=2 |pages=129–135 |doi=10.1016/0925-4005(92)80169-X|bibcode=1992SeAcB...8..129T }} It exhibits electrochromism, changing color when subject to a voltage.
Structure
{{chem2|LuPc2}} is a sandwich compound consisting of a {{chem2|Lu(3+)}} ion coordinated to the conjugate base of two phthalocyanines. The rings are arranged in a staggered conformation. The extremities of the two ligands are slightly distorted outwards.{{cite journal |last1=Bidermane |first1=I. |last2=Lüder |first2=J. |last3=Boudet |first3=S. |last4=Zhang |first4=T. |last5=Ahmadi |first5=S. |last6=Grazioli |first6=C. |last7=Bouvet |first7=M. |last8=Rusz |first8=J. |last9=Sanyal |first9=B. |last10=Eriksson |first10=O. |last11=Brena |first11=B. |last12=Puglia |first12=C. |last13=Witkowski |first13=N. |title=Experimental and theoretical study of electronic structure of lutetium bi-phthalocyanine |journal=The Journal of Chemical Physics |date=21 June 2013 |volume=138 |issue=23 |pages=234701 |doi=10.1063/1.4809725 |pmid=23802970 |bibcode=2013JChPh.138w4701B |url=https://aip.scitation.org/doi/10.1063/1.4809725 |language=en |issn=0021-9606}} The complex features a non-innocent ligand, in the sense that the macrocycles carry an extra electron.{{cite journal |last1=Toupance |first1=Thierry |last2=Plichon |first2=Vincent |last3=Simon |first3=Jacques |title=Substituted bis(phthalocyanines): electrochemical properties and probe beam deflection (mirage) studies |journal=New Journal of Chemistry |date=1999 |volume=23 |issue=10 |pages=1001–1006 |doi=10.1039/A905248H}} It is a free radical with the unpaired electron sitting in a half-filled molecular orbital between the highest occupied and lowest unoccupied orbitals, allowing its electronic properties to be finely tuned.
Properties
{{chem2|LuPc2}}, along with many substituted derivatives like the alkoxy-methyl derivative {{chem2|Lu[(C8H17OCH2)8Pc]2}}, can be deposited as a thin film with intrinsic semiconductor properties; said properties arise due to its radical nature and its low reduction potential compared to other metal phthalocyanines. This initially green film exhibits electrochromism; the oxidized form {{chem2|LuPc2+}} is red, whereas the reduced form {{chem2|LuPc2-}} is blue and the next two reduced forms are dark blue and violet, respectively. The green/red oxidation cycle can be repeated over 10,000 times in aqueous solution with dissolved alkali metal halides, before it is degraded by hydroxide ions; the green/blue redox degrades faster in water.
Electrical properties
{{chem2|LuPc2}} and other lanthanide phthalocyanines are of interest in the development of organic thin-film field-effect transistors.{{cite journal |last1=Wang |first1=Jun |last2=Wang |first2=Haibo |last3=Zhang |first3=Jian |last4=Yan |first4=Xuanjun |last5=Yan |first5=Donghang |title=Organic thin-film transistors with improved characteristics using lutetium bisphthalocyanine as a buffer layer |journal=Journal of Applied Physics |date=15 January 2005 |volume=97 |issue=2 |pages=026106–026106–3 |doi=10.1063/1.1840093|bibcode=2005JAP....97b6106W }}
{{chem2|LuPc2}} derivatives can be selected to change color in the presence of certain molecules, such as in gas detectors; for example, the thioether derivative {{chem2|Lu[(C6H13S)8Pc]2}} changes from green to brownish-purple in the presence of NADH.{{cite journal |last1=Basova |first1=Tamara |last2=Gürek |first2=Ayşe Gül |last3=Ahsen |first3=Vefa |last4=Ray |first4=Asim |title=Electrochromic lutetium phthalocyanine films for in situ detection of NADH |journal=Optical Materials |date=1 January 2013 |volume=35 |issue=3 |pages=634–637 |doi=10.1016/j.optmat.2012.10.017|bibcode=2013OptMa..35..634B }}