First Principles Calculations of Phonon and Thermal Properties
First Principles Calculations of Phonon and Thermal Properties
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声子和热性质的第一原理计算
DOI：
10.11311/jscta.49.3_122
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
東後 篤史
中科院分区：
文献类型：
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作者：
田中 功;東後 篤史
本文对声子计算的第一原理进行了全面的回顾，并对它们在金属和陶瓷科学中的应用特别感兴趣。由于高性能计算机的进步，第一性原理声子计算现在具有可与实验相媲美的精度。它们可以在合理的研究时间框架内使用普通的pc集群来制作。从声子态可以估计出各种热性质。首先，我们描述了恒容、亥姆霍兹能量和熵的调和近似和推导。然后，我们解释了处理声子态的体积依赖性的准谐波近似。可以计算出恒压热容、热膨胀率和吉布斯能。接下来，我们解释了一种通过考虑三阶非调和性来计算晶格导热系数的方法。我们展示了如何通过分析虚声子特征向量来跟踪与相变和变形孪相相关的原子的集体运动。我们还简要描述了自洽声子计算的挑战，包括高阶非调和性和电子-声子相互作用。可靠的声子计算已经成为常规，因为强大的软件的发展和他们的持续维护。最后，举例说明了一些开源代码。
A comprehensive review of the first principles phonon calculations is given here with special interests on their applications to metals and ceramics science. Thanks to the progress of high-performance computers, first principles phonon calculations are now practical with the accuracy comparable to experiments. They can be made using an ordinary PC-cluster within a reasonable research timeframe. A variety of thermal properties can be estimated from the phonon states. Firstly, we describe the harmonic approximation and derivation of heat capacity at constant volume, Helmholtz energy and entropy. Then, we explain the quasi-harmonic approximation that treats volume dependence of phonon states. Heat capacity at constant pressure, thermal expansivity and Gibbs energy can be evaluated. Next, we explain a method to compute lattice thermal conductivity by taking account the third order anharmonicity. We show how to trace the collective motion of atoms associated with phase transitions and deformation twins by analyzing imaginary phonon eigenvectors. We also briefly describe challenges of self-consistent phonon calculations to include higher order anharmonicity and electron-phonon interactions. Reliable phonon calculations have become routine because of the development of robust software and their persistent maintenance. Finally, some open-source codes are exemplified.