Abstract：
Recent theoretical and algorithmic developments have improved the accuracy with which path integral dynamics methods can include nuclear quantum effects in simulations of condensed-phase vibrational spectra. Such methods are now understood to be approximations to the delocalized classical Matsubara dynamics of smooth Feynman paths, which dominate the dynamics of systems such as liquid water at room temperature. Focusing mainly on simulations of liquid water and hexagonal ice, we explain how the recently developed quasicentroid molecular dynamics (QCMD), fast-QCMD, and temperature-elevated path integral coarse-graining simulations (Te PIGS) methods generate classical dynamics on potentials of mean force obtained by averaging over quantum thermal fluctuations. These new methods give very close agreement with one another, and the Te PIGS method has recently yielded excellent agreement with experimentally measured vibrational spectra for liquid water, ice, and the liquid-air interface. We also discuss the limitations of such methods.
摘要：
最近的理论和算法发展提高了路径积分动力学方法可以在凝聚相振动光谱的模拟中包括核量子效应的准确性。现在，这种方法被理解为近似于光滑费曼路径的离域经典Matsubara动力学，在室温下控制液态水等系统的动力学。主要集中在液态水和六边形冰的模拟，我们解释了最近开发的准质心分子动力学(QCMD)，fast-QCMD,和温度升高的路径积分粗粒度模拟（TePIGS）方法在通过对量子热波动求平均而获得的平均力的电势上产生经典动力学。这些新方法彼此非常接近，TePIGS方法最近与实验测量的液态水振动光谱产生了极好的一致性，冰,和液体-空气界面。我们还讨论了这种方法的局限性。
