The thermodynamic properties of a one-dimensional spin-crossover molecular chain under constant external pressure are investigated. The effective compressible degenerate Ising model is used as a theoretical basis. Analytical results for the crossover from low to high spin are obtained using the transfer matrix formalism. Exact expressions are obtained for the fraction of molecules in the high-spin state, the correlation function, and the heat capacity. The analysis of the range of parameters in which the spin-crossover occurs is carried out, and it is shown how the pressure changes the position of the crossover.

中文翻译：

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分子自旋交叉链中压缩的影响

研究了恒定外压下一维自旋交叉分子链的热力学性质。有效可压缩简并Ising模型被用作理论基础。从低自旋到高自旋交叉的分析结果是使用转移矩阵形式获得的。获得了高自旋态分子分数、相关函数和热容的精确表达式。对发生自旋交叉的参数范围进行了分析，显示了压力如何改变交叉位置。