论文标题
物质热容量的微观视图：固体，液体和气体
Microscopic view of heat capacity of matter: solid, liquid, and gas
论文作者
论文摘要
由于强烈的原子相互作用和缺乏对称性，理解原子水平液体的热力学是具有挑战性的。最近的先前理论工作集中在描述液体的热容量在类似语音子的激发方面，但通常依赖于拟合参数和临时假设。在这项工作中，我们对宽度温度范围（高达$ 10^8 $ k）和压力（最高1 tpa）对单个元素系统的分子动力学模拟进行瞬时正常模式和速度自相关进行微观分析。我们的结果表明，液体的热容量可以通过固体样和类似气体的自由度的组合来描述，从而导致统一的框架来描述物质这三个阶段的热容量：固体，液体和气体。
Understanding thermodynamics in liquids at the atomic level is challenging because of strong atomic interactions and lack of symmetry. Recent prior theoretical works have focused on describing heat capacity of liquids in terms of phonon-like excitations but often rely on fitting parameters and ad hoc assumptions. In this work, we perform microscopic analysis on instantaneous normal modes and velocity autocorrelations on molecular dynamics simulations of single element systems over wide ranges of temperature (up to $10^8$ K) and pressure (up to 1 TPa). Our results demonstrate that heat capacity of liquids can be described by a combination of both solid-like and gas-like degrees of freedom, leading to a unified framework to describe heat capacity of all three phases of matter: solid, liquid, and gas.
