Abstract Crystalline α-TeO2 was investigated at ambient pressure using ab initio calculations. The effect of pressure on α-TeO2 was studied from 0 to 10 GPa. The lattice parameters and elastic constants calculated by LDA and GGA method at 0 GPa both agree with the available theoretical and experiment results. The elastic constants Cij, the bulk modulus B, the shear modulus G, Young's modulus E, and the ductile and brittle character (B/G) were calculated and examined in detail. It was found that the calculated universal anisotropy index indicated that α-TeO2 has anisotropy under 0 GPa, and with the pressure increases, its elastic anisotropy increases. Furthermore, from the mechanical stability criteria, it is show that the structure of tetragonal α-TeO2 is not stable above 5.1 GPa. Finally, the electronic and optical properties were also investigated, and the results show that, on increasing the external pressure, the energy bandgap increases, with the optical spectrum exhibiting anisotropy in the x and z directions and a small blue shift under pressure.

中文翻译：

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α-TeO2 在压力下的弹性、电子和光学性质的第一性原理研究

摘要 使用 ab initio 计算在环境压力下研究了结晶 α-TeO2。从 0 到 10 GPa 研究了压力对 α-TeO2 的影响。LDA 和 GGA 方法在 0 GPa 下计算的晶格参数和弹性常数均与现有的理论和实验结果一致。详细计算并检验了弹性常数 Cij、体积模量 B、剪切模量 G、杨氏模量 E 和韧性和脆性特性 (B/G)。发现计算的通用各向异性指数表明α-TeO2在0 GPa以下具有各向异性，并且随着压力的增加，其弹性各向异性增加。此外，从机械稳定性标准来看，四方 α-TeO2 的结构在 5.1 GPa 以上不稳定。最后，