论文标题
绝缘子 - 金属过渡边界的完全一致的密度功能理论的确定在温暖的氢气中
Fully Consistent Density Functional Theory Determination of the Insulator-Metal Transition Boundary in Warm Dense Hydrogen
论文作者
论文摘要
使用概念和程序上一致的密度功能理论（DFT）计算，在从头算分子动力学模拟中具有先进的元ggGA交换和相关功能，我们确定了在压力范围50至300 GPA上，温暖致密流体氢的绝缘液 - 金属转变（IMT）。通过途径综合分子动力学（PIMD）纳入核量子效应，可增强金属过渡，并降低相对于Born-Oppenheimer（BO）MD产生的过渡温度。与先前的DFT预测相比，BOMD本身与实验结果的一致性提高了。在过渡时突然电导率上升的情况下，对离子对相关函数的检查证实，由于分子氢的解离，与突然的带隙闭合相吻合。 PIMD和BOMD结果的直接比较清楚地表明了对IMT的同位素效应。这些结果与随机模拟不同，不取决于基本状态和有限T方法的任何临时组合。
Using conceptually and procedurally consistent density functional theory (DFT) calculations with an advanced meta-GGA exchange-correlation functional in ab initio molecular dynamics simulations, we determine the insulator-metal transition (IMT) of warm dense fluid hydrogen over the pressure range 50 to 300 GPa. Inclusion of nuclear quantum effects via path-integral molecular dynamics (PIMD) sharpens the metallic transition and lowers the transition temperature relative to results from Born-Oppenheimer (BO) MD. BOMD itself gives improved agreement with experimental results compared to previous DFT predictions. Examination of the ionic pair correlation function in the context of the abrupt conductivity increase at the transition confirms a metallic transition due to the dissociation of molecular hydrogen that coincides with an abrupt band gap closure. Direct comparison of the PIMD and BOMD results clearly demonstrates an isotope effect on the IMT. Distinct from stochastic simulations, these results do not depend upon any ad hoc combination of ground-state and finite-T methodologies.
