Elasticity of Diamond at High Pressures and Temperatures
Elasticity of Diamond at High Pressures and Temperatures
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DOI：
10.1063/1.4754548
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发表时间：
2012-05
期刊：
影响因子：
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通讯作者：
M. Valdez;K. Umemoto;R. Wentzcovitch
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文献类型：
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作者：
M. Valdez;K. Umemoto;R. Wentzcovitch
我们将密度泛函理论与局域密度近似、准谐近似和振动态密度相结合，计算了金刚石在0-500 Gpa和0-4800K的同时高压和高温下的单晶弹性常数、体弹性系数和剪切弹性系数，并与常压和高温下的实验值进行了比较，首次与第一性原理的结果相吻合，验证了我们的方法。结果表明，在高压下，金刚石的各向异性因子增加到40%，并且与温度无关。
We combine density functional theory within the local density approximation, the quasiharmonic approximation, and vibrational density of states to calculate single crystal elastic constants, and bulk and shear moduli of diamond at simultaneous high pressures and temperatures in the ranges of 0-500 GPa and 0-4800 K. Comparison with experimental values at ambient pressure and high temperature shows an excellent agreement for the first time with our first-principles results validating our method. We show that the anisotropy factor of diamond increases to 40% at high pressures and becomes temperature independent.