适用于钠的宽温深势模型：从熔点到临界点的近实验精度温度依赖模型
A wide-range temperature-dependent deep potential for sodium with near-experimental accuracy from melting to the critical point
- Joint Institute for High Temperatures（高温物理联合研究所）
- Moscow Institute of Physics and Technology（莫斯科物理技术学院）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究构建了基于不同泛函的钠温度依赖深势模型，通过模拟得到近实验精度的钠热物理性质，扩展了输运数据并验证了结果的热力学一致性。
AI中文摘要：
我们采用PBE、AM05和$r^2$SCAN交换关联泛函得到的有限温度DFT数据，构建了钠的温度依赖深势模型，并研究了钠从室温到临界区的热物理性质。预测的临界参数对交换关联泛函存在依赖：基于$r^2$SCAN泛函的模型给出临界温度$T_c=2.508(8)$ kK、密度$\rho_c=0.203(4)$ g/cm³、压力$P_c=0.249(6)$ kbar，与推荐值吻合度高。该模型被用于重建常压和临界等压线，并计算焓、热容、热膨胀系数、体模量、格林艾森参数和声速；计算得到的常压体心立方（bcc）密度与实验值仅相差0.06%。直接固液共存模拟得到熔点为346(2) K，比推荐值低25 K，与每原子meV级自由能误差的预期敏感性一致。液气共存模拟重现了双结点曲线，并在临界点附近表面张力趋近于零。计算得到的自扩散系数和剪切黏度将可用的输运性质数据扩展到膨胀液体和近临界区，该区域直接实验信息匮乏。我们还通过对比直接声学模拟得到的声速与从物态方程计算得到的声速，验证了结果的热力学一致性。
英文摘要：
We construct temperature-dependent deep potentials for sodium using finite-temperature DFT data obtained with the PBE, AM05, and $r^2$SCAN exchange-correlation functionals and investigate the thermophysical properties of sodium from room temperature to the critical region. The predicted critical parameters show a dependence on the exchange-correlation functional. The model based on the $r^2$SCAN functional gives a critical temperature $T_c=2.508(8)$ kK, density $ρ_c=0.203(4)$ g/cm$^{3}$, and pressure $P_c=0.249(6)$ kbar, in close agreement with the recommended values. This model is then used to reconstruct the normal-pressure and critical isobars and to calculate the enthalpy, heat capacities, thermal expansion coefficient, bulk moduli, Grüneisen parameter, and speed of sound. The calculated normal-pressure bcc density differs by only 0.06% from the experimental value. Direct solid-liquid coexistence simulations give a melting temperature of $346(2)$ K, 25 K below the recommended value, consistent with the sensitivity expected from meV/atom free-energy errors. Liquid-vapor coexistence simulations reproduce the binodal and yield a surface tension that approaches zero near the critical point. The calculated self-diffusion coefficient and shear viscosity extend the available transport-property data into the expanded-liquid and near-critical regions, where direct experimental information is sparse. We also demonstrate the thermodynamic consistency of the results by comparing the speed of sound obtained from direct acoustic simulations with that calculated from the equation of state.
