Abstract

The structural, mechanical and thermal properties of perovskite BaZrS₃ have been investigated in terms of first-principles plane-wave pseudopotential method. Four structures such as GdFeO₃-type, BaNiO₃-type, NH₄CdCl₃-type and CaTiO₃-type structures are considered. The results show that the calculated lattice structural results of perovskite BaZrS₃ with the GdFeO₃-type phase are in good agreement with the available experimental data. It is predicted that those structures are thermodynamically stable. The structural stability order of the four phases is GdFeO₃-type > NH₄CdCl₃-type > CaTiO₃-type > BaNiO₃-type from the calculated formation energies. The elastic constants of the four structures prove that GdFeO₃-type, NH₄CdCl₃-type and CaTiO₃-type structures are mechanically stable while the BaNiO₃-type structure is mechanically unstable. The mechanical properties of perovskite BaZrS₃ such as the bulk modulus, shear modulus, Young’s modulus and elastic anisotropy were calculated from the obtained elastic constants. The analysis of B/G ratio confirms that perovskite BaZrS₃ is ductile materials. In particular, we firstly report the theoretical prediction of the thermal properties including Debye temperature and melting temperature of perovskite BaZrS₃.

Graphical abstract

中文翻译：

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钙钛矿BaZrS 3的结构，力学和热学性质的第一性原理预测

摘要

钙钛矿BaZrS ₃的结构，力学和热学性质已通过第一性原理平面波plane势法进行了研究。考虑了四种结构，例如GdFeO ₃型，BaNiO ₃型，NH ₄ CdCl ₃型和CaTiO ₃型结构。结果表明，具有GdFeO ₃型相的钙钛矿BaZrS _3的晶格结构计算结果与现有实验数据吻合良好。据预测，这些结构是热力学稳定的。四个相的结构稳定性顺序为GdFeO ₃型> NH ₄ CdCl₃型>的CaTiO ₃型> BaNiO ₃型从计算出的形成能。四个结构的弹性常数证明GdFeO ₃型，NH ₄的CdCl ₃型和的CaTiO ₃型结构是机械稳定的，而BaNiO ₃型结构在机械上不稳定。由获得的弹性常数计算钙钛矿BaZrS ₃的机械性能，例如体积模量，剪切模量，杨氏模量和弹性各向异性。B / G比的分析证实钙钛矿BaZrS ₃是韧性材料。特别是，我们首先报道了热性能的理论预测，包括钙钛矿BaZrS _3的德拜温度和熔化温度。

图形概要