title: Photomagnetic response in highly conductive iron(II) spin-crossover complexes with TCNQ radicals.
abstract: Co-crystallization of a cationic Fe(II) complex with a partially charged TCNQ(.δ-) (7,7',8,8'-tetracyanoquinodimethane) radical anion has afforded molecular materials that behave as narrow band-gap semiconductors, [Fe(tpma)(xbim)](X)(TCNQ)(1.5)⋅DMF (X=ClO4(-) or BF4(-); tpma=tris(2-pyridylmethyl)amine, xbim=1,1'-(α,α'-o-xylyl)-2,2'-bisimidazole). Remarkably, these complexes also exhibit temperature-and light-driven spin crossover at the Fe(II) center, and are thus the first structurally defined magnetically bistable semiconductors assembled with the TCNQ(.δ-) radical anion. Transport measurements reveal the conductivity of 0.2 S cm(-1) at 300 K, with the low activation energy of 0.11 eV.
authors.affiliation: Department of Chemistry & Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306 (USA) http://www.chem.fsu.edu/∼shatruk/
authors.forename: Hoa
authors.initials: H
authors.lastname: Phan
authors.forename: Shermane M
authors.initials: SM
authors.lastname: Benjamin
authors.forename: Eden
authors.initials: E
authors.lastname: Steven
authors.forename: James S
authors.initials: JS
authors.lastname: Brooks
authors.forename: Michael
authors.initials: M
authors.lastname: Shatruk
keywords: TCNQ; conductivity; iron; semiconductors; spin crossover