Abstract To understand the interplay between lattice structure and spin degrees of freedom, a bulk-Gd lattice as a hexagonal close-packed structure was generated and populated with paramagnetic Gd3+ ions with random projections (MSGd(i), i = 1, 245, or 443). Isotropic interactions of every site with their 12 nearest neighbors were taken into account. On the basis of the Monte Carlo Metropolis algorithm, the variation with temperature and magnetic field strength was obtained for the following physical quantities: magnetization M(T,H), the product of the magnetic susceptibility and temperature χ m o l ∗ T , magnetic specific heat C(T,H), entropy variation Δ S ( T , Δ H ) , and statistics of spin projections MSGd(i,T). We also show the resulting interatomic exchange J G d − G d , the reorientation of the spin temperature, the behavior of the Curie temperature versus a magnetic field, and magnetocaloric properties of bulk Gd.

中文翻译：

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块状 Gd 的 Monte Carlo 建模

摘要 为了理解晶格结构和自旋自由度之间的相互作用，生成了作为六方密堆积结构的体 Gd 晶格，并填充了具有随机投影的顺磁性 Gd3+ 离子 (MSGd(i), i = 1, 245, or第443页。考虑了每个站点与其 12 个最近邻站点的各向同性相互作用。基于Monte Carlo Metropolis算法，得到以下物理量随温度和磁场强度的变化：磁化强度M(T,H)，磁化率与温度的乘积χ mol ∗ T，磁比热C(T,H)、熵变 Δ S ( T , Δ H ) 和自旋投影 MSGd(i,T) 的统计。我们还展示了由此产生的原子间交换 JG d - G d ，自旋温度的重新定向，