%A Rodríguez-Castellanos, C.
%A Plasencia-Montesinos, Y.
%A Reguera-Ruiz, E. F.
%D 2018
%T Spin- Crossover in Molecular Crystals: An Electron- Coupled Local Vibrations Model
%B 2018
%9
%! Spin- Crossover in Molecular Crystals: An Electron- Coupled Local Vibrations Model
%K
%X A model of eg electrons at octahedral sites coupled to local vibrational “breathing” modes interacting with its near neighbors is proposed to describe spin-crossover (SCO) in molecular crystals. Decoupling vibrations leads to an effective electron Hamiltonian with renormalized site energies, where ferromagnetic and antiferromagnetic, short range and long range electron-electron interactions arise in a natural way. An exact analytic expression for the free energy functional is derived. A phase diagram for homogenous phases, describing the basic phenomenology of SCO is obtained and the transition temperatures are expressed in terms of model parameters. Under appropriate conditions, two-step transitions are found to take place for systems with both, short range and long range interactions. Stability with respect to spatial fluctuations is discussed.
%U http://revistacubanadefisica.org/index.php/rcf/article/view?path=
%J Revista Cubana de Física
%0 Journal Article
%& 91
%P 6
%V 35
%N 2
%@ 2224-7939
%8 2018-12-15
%7 2018-12-14