Cooperative Phenomena in Spin Crossover Systems
Abstract
Within the framework of a realistic multi-band p-d-model, we derived an effective Hamiltonian to describe the exchange interaction effects near the spin crossover in magnetic Mott-Hubbard insulators under pressure. It is shown that single-ion mechanism of spin crossover under change of the crystal field does not lead to a thermodynamic phase transition, however, at T = 0 a quantum phase transition appears. It has been found that the cooperativity leads to a modification of the quantum phase transition to a first-order phase transition and the appearance of metastable states of the system. The pressure - temperature phase diagram has been obtained to describe the magnetization and high-spin population near the spin crossover of the Motts dielectrics with d6-ions.
Cite
@article{arxiv.1611.10009,
title = {Cooperative Phenomena in Spin Crossover Systems},
author = {Alexander I. Nesterov and Yuri S. Orlov and Sergey G. Ovchinnikov and Sergey V. Nikolaev},
journal= {arXiv preprint arXiv:1611.10009},
year = {2017}
}
Comments
This paper has been withdrawn by the author due to a crucial error in equation 31