In this work, theoretically study of structural, elastic, and mechanical properties of Terbium monopnictides TbX (X = P, As) in NaCl– B1 and CsCl–B2 phases are investigated using IIPM model. This model consists of Columbic interaction, three body interaction, polarizability effect and overlapping repulsive interaction operative up to second nearest neighbor. TbP and TbAs compounds exhibit structural phase transition from B1 to B2 phase at 46.3 GPa and 16.1 GPa pressure, respectively. The calculated structural phase transition pressures, bulk modulus and second order elastic constants are presented. Elastic constants and their related parameters such as Poisson's ratio, Young modulus and Shear modulus were also calculated. We have also predicted the pressure variation of the elastic and bulk modulus for B1 structure. We have compared our results with the available experimental and theoretical data.

在这项工作中，使用 IIPM 模型研究了在 NaCl-B1 和 CsCl-B2 相中单核铽 TbX（X = P，As）的结构、弹性和机械性能的理论研究。该模型由 Columbic 相互作用、三体相互作用、极化效应和重叠排斥相互作用组成，可操作至第二最近邻。TbP 和 TbAs 化合物分别在 46.3 GPa 和 16.1 GPa 压力下表现出从 B1 相到 B2 相的结构相变。给出了计算的结构相变压力、体积模量和二阶弹性常数。还计算了弹性常数及其相关参数，如泊松比、杨氏模量和剪切模量。我们还预测了 B1 结构的弹性和体积模量的压力变化。