Pressure-induced two-step spin crossover in a double-layered elastic model
Pressure-induced two-step spin crossover in a double-layered elastic model
复制标题
双层弹性模型中压力诱导的两步自旋交叉
DOI：
10.1103/physrevb.96.174104
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发表时间：
2017
影响因子：
3.7
通讯作者：
Hotta Chisa
中科院分区：
文献类型：
--
作者：
Taniguchi Daisuke;Okabayashi Jun;Hotta Chisa
本文研究了过渡金属配合物处于高自旋（HS）态和低自旋（LS）态的双层弹性模型中的两步自旋交叉。在NPT-MonteCarlo方法框架内，只考虑相邻分子间最简单的弹性相互作用，系统暴露于外压下。当施加一定量的压力时，均匀HS和LS相之间的一级热转变转变为具有新兴中间自旋（IS）相的两步转变，其中HS和LS分子在层之间面对面配对并且在层内形成对角条纹簇。HS和LS分子大小的差异反映在弹性相互作用和焓中，IS相可以通过显着减小其体积来获得后者而不是前者的损失。将目前的压力效应解释为双层过渡金属材料中的化学效应，这实际上揭示了与我们的数值结果相关的多种多步自旋交叉转变。
We study the two-step spin crossover in a double-layered elastic model based on transition metal complexes each taking high spin (HS) and low spin (LS) states. Here, only the simplest elastic interactions between adjacent molecules are considered, and the system is exposed to the external pressure within the framework ofNPT-Monte Carlo method. As a certain amount of pressure is applied, the first order thermal transition between uniform HS and LS phases transforms to a two-step transition with an emergent intermediate spin (IS) phase, where the HS and LS molecules are paired face to face between layers and form diagonally striped clusters within the layer. The difference in the size of HS and LS molecules is reflected both in the elastic interactions and in the enthalpy, and the IS phase could gain the latter over the loss of the former by significantly reducing its volume. The present pressure effect is interpreted to the chemical one in double-layered transition metal materials, which actually reveals a variety of multistep spin crossover transitions relevant to our numerical result.