title: High-spin to low-spin relaxation kinetics in the [Fe(TRIM)2]Cl2 complex.
abstract: A quasi-quantitative photo-induced low-spin (LS)-->high-spin (HS) conversion of FeII ions has been observed in the [Fe(TRIM)2]Cl2 complex by irradiating the sample with blue light (488 nm) at 10 K. The time dependence of the HS-->LS relaxation has been studied between 10 K and 44 K by means of magnetic susceptibility measurements. These relaxation curves could be satisfactorily fitted by mono-exponential decays including tunnelling effect except for temperatures below 30 K. The introduction of a distribution of vibrational frequencies into this model improved significantly the fits in the low-temperature range and gave a good agreement with the experimental data in the whole temperature range suggesting a multi-rate relaxation process in this complex.
authors.affiliation: Laboratoire de Chimie de Coordination, UPR 8241 CNRS, 205 route de Narbonne, F-31077, Toulouse Cedex, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Bonhommeau
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bréfuel
authors.forename: Villö K
authors.initials: VK
authors.lastname: Pálfi
authors.forename: Gábor
authors.initials: G
authors.lastname: Molnár
authors.forename: Antoine
authors.initials: A
authors.lastname: Zwick
authors.forename: Lionel
authors.initials: L
authors.lastname: Salmon
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Tuchagues
authors.forename: José
authors.initials: J
authors.lastname: Sanchez Costa
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Létard
authors.forename: Hauke
authors.initials: H
authors.lastname: Paulsen
authors.forename: Azzedine
authors.initials: A
authors.lastname: Bousseksou
mesh_terms: D000465:Algorithms; D002712:Chlorides; D005290:Ferric Compounds / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry*; D007700:Kinetics; D013059:Spectrum Analysis, Raman / Q000379:methods; D013113:Spin Labels; D013696:Temperature; D014732:Vibration
chemical_list: D002712:Chlorides; D005290:Ferric Compounds; D007093:Imidazoles; D013113:Spin Labels; C024555:ferric chloride