title: High-spin- and low-spin-state structures of [Fe(chloroethyltetrazole)6](ClO4)2 from synchrotron powder diffraction data.
abstract: The spin-crossover complex [Fe(teec)(6)](ClO(4))(2) (teec = chloroethyltetrazole) exhibits a 50 % incomplete spin crossover in the temperature range 300-30 K. Time-resolved synchrotron powder diffraction experiments have been carried out to elucidate its structural behavior. We report crystal structure models of this material at 300 K (high spin) and 90 K (low spin), as solved from synchrotron powder diffraction data by using Genetic Algorithm and Parallel Tempering techniques and refined with Rietveld refinement. During short synchrotron powder diffraction experiments (five minutes duration) two distinguishable lattices were observed the quantities of which vary with temperature. The implication of this phenomenon, that is interpreted as a structural phase transition associated with the high-to-low spin crossover, and the structural characteristics of the high-spin and low-spin models are discussed in relation to other compounds showing a similar type of spin-crossover behavior.
authors.affiliation: University of Amsterdam, Faculty of Science van't Hoff Institute for Molecular Sciences, Laboratory for Crystallography, Valckenierstraat 65, 1018 XE, Amsterdam, The Netherlands. eva@science.uva.nl
authors.forename: Eva
authors.initials: E
authors.lastname: Dova
authors.forename: René
authors.initials: R
authors.lastname: Peschar
authors.forename: Makoto
authors.initials: M
authors.lastname: Sakata
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kato
authors.forename: Henk
authors.initials: H
authors.lastname: Schenk