Szałowski Karol, Kowalewska Pamela
Department of Solid State Physics, Faculty of Physics and Applied Informatics, University of Lodz, ulica Pomorska 149/153, PL90-236 Łódź, Poland.
Materials (Basel). 2020 Jan 19;13(2):485. doi: 10.3390/ma13020485.
We calculated the magnetocaloric properties of the molecular nanomagnet Cu5-NIPA, consisting of five spins S = 1 / 2 arranged in two corner-sharing triangles (hourglass-like structure without magnetic frustration). The thermodynamics of the system in question was described using the quantum Heisenberg model solved within the field ensemble (canonical ensemble) using exact numerical diagonalization. The dependence of the magnetic entropy and magnetic specific heat on the temperature and the external magnetic field was investigated. The isothermal entropy change for a wide range of initial and final magnetic fields was discussed. Due to plateau-like behavior of the isothermal entropy change as a function of the temperature, a high degree of tunability of magnetocaloric effect with the initial and final magnetic field was demonstrated.
我们计算了分子纳米磁体Cu5-NIPA的磁热性质，该磁体由五个自旋S = 1/2组成，排列在两个角共享三角形中（类似沙漏的结构，没有磁阻挫）。使用在场系综（正则系综）内通过精确数值对角化求解的量子海森堡模型描述了该系统的热力学。研究了磁熵和磁比热对温度和外部磁场的依赖性。讨论了在很宽的初始和最终磁场范围内的等温熵变。由于等温熵变随温度的函数呈现出类似平台的行为，证明了磁热效应随初始和最终磁场具有高度的可调性。
