We propose a theoretical Hugoniot obtained by combining results for the equation of state (EOS) from the Direct Path Integral Monte Carlo technique (DPIMC) and those from Reaction Ensemble Monte Carlo (REMC) simulations. The main idea of such proposal is based on the fact that DPMIC provides first-principle results for a wide range of densities and temperatures including the region of partially ionized plasmas. On the other hand, for lower temperatures where the formation of molecules becomes dominant, DPIMC simulations become cumbersome and inefficient. For this region it is possible to use accurate REMC simulations where bound states (molecules) are treated on the Born-Oppenheimer level using a binding potential calculated by Kolos and Wolniewicz. The remaining interaction is then reduced to the scattering between neutral particles which is reliably treated classically applying effective potentials. The resulting Hugoniot is located between the experimental values of Knudson {\textit{et al.}} \cite{1} and Collins {\textit{et al.}} \cite{2}.
Thermal and Pressure Ionization in Warm, Dense MgSiO$_3$ Studied with First-Principles Computer Simulations
利用路径积分蒙特卡罗和密度泛函分子动力学(DFT-MD)模拟方法,研究了MgSiO $_3$顽火辉石在暖稠密物质区的性质.我们产生了一个一致的状态方程(EOS),跨越了很宽的温度和密度范围(10 $^4$-10 $^7$ K和6.42- 64.16 g cm $^{-3}$)。导出了冲击Hugoniot曲线,与实验符合得很好。我们确定的边界之间的制度的热电离和压力电离的定位在恒定温度下的内能达到最小值作为密度或压力的函数。在低密度下,随着自由态重量的变化,内能随着密度的增加而减小。热电离占主导地位。相反地,在高密度下,在压力电离状态下,内能随密度增加。我们确定两个制度之间的边界,并表明,压缩最大值沿冲击Hugoniot曲线发生,因为K壳层电子成为热电离,而不是压力电离。
First-Principles Simulations of Warm Dense Lithium Fluoride
我们进行第一性原理路径积分蒙特卡罗(PIMC)和密度泛函理论分子动力学(DFT-MD)计算,以探索温暖的致密物质状态的LiF。我们的模拟覆盖了$2.08-15.70$ ~g、$\,$、cm、$^{-3}$和$10^4-10^9$ ~K的宽密度-温度范围。由于PIMC和DFT-MD精确地处理原子壳层结构的影响,我们发现一个明显的压缩最大值和一个肩膀上的主要Hugoniot曲线归因于K-壳层和L-壳层电离。结果为广泛使用的EOS表,如SEEOS,LEOS和模型提供了基准。此外,我们计算对关联函数,揭示了一个不断变化的等离子体结构和电离过程,驱动的热和压力电离。最后,我们计算电子态密度的液体LiF的DFT-MD模拟,并发现,电子间隙可以保持开放的密度和温度增加到至少15.7克$~$ cm $^{-3}$。
Deep Learning-Accelerated Dynamic Kinetic Monte Carlo Simulation for Hydrogen Transport in Tungsten
Yamagata University(山形大学);National Institute for Fusion Science(国立研究開発法人核融合科学研究所);Nagoya University(名古屋大学);Toyota Technical Development Corporation(丰田技术开发株式会社);Keio University(庆应义塾大学);National Institutes for Quantum Science and Technology(国立研究開発法人量子科学技術研究開発機構);National Institutes of Technology, Nagaoka College(国立高等専門学校機構長岡工業高等専門学校)
用费米子路径积分蒙特卡罗模拟方法研究了氢和氘在1.6 < rs < 14.0和5000 K < T <167000 K的密度和温度范围内的平衡性质。我们使用这种技术来确定相图通过识别等离子体,分子,原子和金属制度。我们解释了如何可以识别的阶段,在路径积分形式主义和讨论的状态,氢的温度-密度平面上的5个点。此外,我们将提供的政权之间的过渡性质的参数。