UNIGE document Scientific Article
previous document  unige:3304  next document
add to browser collection
Title

Low-temperature lifetimes of metastable high-spin states in spin-crossover and in low-spin iron(II) compounds: The rule and exceptions to the rule

Authors
Amstutz, Nahid
Published in Coordination Chemistry Reviews. 2006, vol. 250, no. 13-14, p. 1642-1652
Abstract The high-spin → low-spin relaxation in spin-crossover compounds can be described as non-adiabatic multi-phonon process in the strong coupling limit, in which the low-temperature tunnelling rate increases exponentially with the zero-point energy difference between the two states. Based on the hypothesis that the experimental bond length difference between the high-spin and the low-spin state of not, vert, similar0.2 Å is also valid for low-spin iron(II) complexes, extrapolation of the single configurational coordinate model allows an estimate of the zero-point energy difference for low-spin complexes from kinetic data. DFT calculations on low-spin [Fe(bpy)3]2+ support the structural assumption. However, for low-spin [Fe(terpy)2]2+ the relaxation rate constant shows an anomalous behaviour in so far as it is more in line with spin-crossover systems. This is attributed to very anisotropic bond length changes associated with the spin state change, and the subsequent breakdown of the single mode model.
Keywords Spin-crossoverIntersystem crossingRadiationless relaxationDensity functional theoryIron(II)-tris-2,2'-bipyridineIron(II)-bis-2,2':6',2″-terpyridine
Identifiers
Full text
Structures
Research group Groupe Hauser
Citation
(ISO format)
HAUSER, Andreas et al. Low-temperature lifetimes of metastable high-spin states in spin-crossover and in low-spin iron(II) compounds: The rule and exceptions to the rule. In: Coordination Chemistry Reviews, 2006, vol. 250, n° 13-14, p. 1642-1652. https://archive-ouverte.unige.ch/unige:3304

314 hits

255 downloads

Update

Deposited on : 2009-09-21

Export document
Format :
Citation style :