Thermal expansion in insulating solids from first principles
Thermal expansion in insulating solids from first principles
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从第一原理了解绝缘固体的热膨胀
DOI：
10.1063/1.5125779
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发表时间：
2019
影响因子：
3.2
通讯作者：
N. Benedek
中科院分区：
文献类型：
--
作者：
E. Ritz;Sabrina J. Li;N. Benedek
在这篇文章中，我们描述了使用准谐波近似和第一性原理密度泛函理论（DFT）来计算和分析绝缘固体的热膨胀。我们讨论的理论基础的准谐波近似，并证明其实际使用中的两个常见的框架内计算热膨胀：亥姆霍兹自由能框架和Gruneisen理论。以硅为例，我们提供了一个指南，用于预测晶格参数如何使用DFT作为温度的函数变化，包括声子模式和声子态密度，弹性常数和比热的计算。我们还描述了Gruneisen参数的计算和解释，以及它们如何与热膨胀系数。准谐波近似的局限性简要触及，以及与实验数据的理论结果的比较。最后，我们用铁电PbTiO 3的例子来说明如何使用的方法可以适应于研究各向异性系统。
In this Tutorial, we describe the use of the quasiharmonic approximation and first-principles density functional theory (DFT) to calculate and analyze the thermal expansion of insulating solids. We discuss the theory underlying the quasiharmonic approximation and demonstrate its practical use within two common frameworks for calculating thermal expansion: the Helmholtz free energy framework and the Gruneisen theory. Using the example of silicon, we provide a guide for predicting how the lattice parameter changes as a function of temperature using DFT, including the calculation of phonon modes and phonon density of states, elastic constants, and specific heat. We also describe the calculation and interpretation of Gruneisen parameters, as well as how they relate to coefficients of thermal expansion. The limitations of the quasiharmonic approximation are briefly touched on, as well as the comparison of theoretical results with experimental data. Finally, we use the example of ferroelectric PbTiO 3 to illustrate how the methods used can be adapted to study anisotropic systems.
影响因子：
15
作者：
Goodwin, Andrew L.;Kennedy, Brendan J.;Kepert, Cameron J.
通讯作者：
Kepert, Cameron J.