Cooperative phenomena in spin crossover systems

Article

关键词: ISING-LIKE MODEL;    EARTHS LOWER MANTLE;    MEAN-FIELD APPROACH;    HIGH-PRESSURE;    LONG-RANGE;    DYNAMICAL MODEL;    TRANSITION;    STATE;    BAND;    SOLIDS;   

DOI  :  10.1103/PhysRevB.96.134103

来源: SCIE

【 摘 要 】

Within the framework of a realistic multiband 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 the single-ion mechanism of spin crossover under the change in 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 Mott's insulators with d(6) ions.

【 授权许可】

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