压力和温度取决于的初始和准和的热弹性特性
Xuejun Gong1,2, Andrea Dal Corso1,2
1SISSA, Via Bonomea 265, I-34136 Trieste, Italy.
概括
这项研究详细介绍了以身体为中心的立方的温度和压力依赖的热弹性特性,与弹性常数和剪切声速的实验数据有很好的一致性.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 计算材料科学科学 计算材料科学
背景情况:
- 了解耐火金属如的热弹性特性对于高温应用至关重要.
- 需要准确的理论预测来补充实验数据,特别是在极端条件下.
研究的目的:
- 为了计算ab initio温度和压力依赖的体中心立方的热弹性特性.
- 研究声和电子激发对自由能量的贡献.
- 将理论预测与现有的实验数据进行比较.
主要方法:
- 使用ab initio计算与近似和近似.
- 在各种参考体积下计算弹性常数 (EC).
- 对不同温度和压力进行EC间波.
- 使用PBE和PBEsol函数来进行比较.
主要成果:
- 理论弹性常数与环境压力下的实验数据有很好的一致性.
- 剪切声速的压力和温度依赖性与实验测量很好地一致.
- 在高温下压缩速度的差异归因于散装模量温度导数.
结论:
- 最初的准和方法准确地预测了的热弹性特性.
- 无论是PBE和PBEsol的功能性都显示出类似的趋势,PBEsol在0K显示出更好的协议.
- 需要进一步精细化才能完全捕捉高温压缩速度的行为.
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