Thermodynamic properties of molecular quantum-magnets by series expansion

本课题致力于对超分子固体的磁性与结构之间的关系进行实验与理论相结合的研究。我们打算从三个方面来研究这种相关性。首先，利用高达1 GPa的外部压力分析准二维化合物（CH3NH3）2CuCl4的弹性和非弹性中子散射响应，以及通过压力诱导铁/反铁磁体跃迁调谐后的磁化率。其次，我们将研究具有铁磁链内偶联的准一维双金属链化合物MnNi(NO2)4(en)2, （en=乙二胺）的结构，以及静态和动态磁性能随外部压力的变化，以揭示压力敏感性以及链间和链内交换之间的相互作用。最后，我们将通过考虑磁性、量子相图和锯齿形混合自旋阶梯模型的自旋动力学，研究双金属体系中磁相关性作为链间耦合函数的演化。

This project is devoted to a combined experimental and theoretical study of the correlation between the magnetism and structure of supramolecular solids. We intend to investigate this correlation along three lines. First, external pressure up to 1 GPa will be used to analyze both, the elastic and inelastic neutron scattering response, and moreover the magnetic susceptibility upon tuning through a pressure induced ferro/antiferromagnet transition in the quasi two-dimensional compound (CH3NH3)2CuCl4. Second, we will investigate the structure, and the static and dynamic magnetic properties as function of external pressure for the quasi one-dimensional bimetallic chain-compound MnNi(NO2)4(en)2, (en=ethylendiamine) with ferromagnetic intra-chain coupling in order to reveal the pressure sensitivity and the interplay between inter- and intra-chain exchange. Finally we will study the evolution of magnetic correlations as a function of inter-chain coupling in bimetallic systems by considering the magnetism, the quantum-phase diagram, and the spin-dynamics of zig-zag mixed-spin-ladder models.