论文标题
$ \ textit {ab intib} $立方casio $ _3 $ perovskite的Anharmonic热力学特性
$\textit{Ab initio}$ anharmonic thermodynamic properties of cubic CaSiO$_3$ perovskite
论文作者
论文摘要
我们提出了一个$ \ textit {ab intio} $研究Cubic Casio $ _3 $ perovskite（CAPV）的热力学特性（CAPV）的压力和温度范围。我们通过利用声子准颗粒方法来计算整个布里鲁因区域的非谐声子分散，该方法表征了声子频率的内在温度依赖性，并原则上捕获了完全的非谐度。这种与温度有关的声子分散剂用于计算$ \ textit {ab intio} $自由能在声音气体模型的框架内的热力学极限（$ n \ rightarrow \ infty $）中。准确的自由能计算使我们能够研究Cubic CAPV的热力学特性和状态的热方程，并在其中证明了呼吸效应。目前的方法为探索高压和温度下强烈的静脉材料的相位边界，热弹性和热弹性特性提供了重要的理论方法。
We present an $\textit{ab initio}$ study of the thermodynamic properties of cubic CaSiO$_3$ perovskite (CaPv) over the pressure and temperature range of the Earth's lower mantle. We compute the anharmonic phonon dispersions throughout the Brillouin zone by utilizing the phonon quasiparticle approach, which characterizes the intrinsic temperature dependence of phonon frequencies and, in principle, captures full anharmonicity. Such temperature-dependent phonon dispersions are used to calculate $\textit{ab initio}$ free energy in the thermodynamic limit ($N \rightarrow \infty$) within the framework of the phonon gas model. Accurate free energy calculations enable us to investigate cubic CaPv's thermodynamic properties and thermal equation of state, where anharmonic effects are demonstrated. The present methodology provides an important theoretical approach for exploring phase boundaries, thermodynamic, and thermoelastic properties of strongly anharmonic materials at high pressures and temperatures.
