Description of spin-crossover in a heterogeneous chain of exchangE clusterS
V. A. Morozov
International Tomography Center, Siberian Division, Russian Academy of Sciences, Novosibirsk
Keywords: molecular magnetics, exchange cluster, spin-crossover, effective magnetic moment
Abstract
Spin transition theory is developed for periodic chains with two and more exchange clusters in a unit cell. A general expression is obtained for the effective magnetic moment of a unit cell μeff with several exchange clusters. For heterospin complexes Cu(hfac)2LR characterized by chains with the head-to-head motif a two-site approximation for the statistical sum of the Cu2+ Jahn – Teller paramagnetic center Cu2+ with spin 1/2 is proposed, within which a comparison with the available experimental data is performed. It is shown that the model developed describes both smooth and abrupt (cooperative) spin-crossover cases for the chains of three-spin exchange clusters.
|
