论文标题
核量子效应：它们与液态水中子衍射研究的相关性
Nuclear quantum effects: their relevance in neutron diffraction studies of liquid water
论文作者
论文摘要
已经计算了针对光（H2O），重（D2O）和NULL（H1.28D0.72O）水的经典分子动力学（MD）模拟模型的核量子效应（NQE）的校正。还针对同一系统进行了新的路径积分分子动力学（PIMD）模拟。 NQE对重水的O-D和D-D部分径向分布功能的影响要小于对浅水的O-H和H-H。校正NQE后，轻质和重水中的O-H键长也不同：O-D键比O-H的键短约0.5％。遵循NQE校正后，零水的总RDF确实在分子内O-H峰位置显示出与氢相关的特征。基于涉及NQE校正的总和部分径向分布函数的交叉检查程序，可以说，关于液体水的结构，H和D相等的假设对分子间相关的非常好的近似值是有效的。这些发现也得到了我们的路径积分分子动力学模拟的支持。
Corrections for nuclear quantum effects (NQE) have been calculated for classical molecular dynamics (MD) simulation models of light (H2O), heavy (D2O) and null (H1.28D0.72O) water. New path integral molecular dynamics (PIMD) simulations have also been conducted for the same systems. NQEs have somewhat smaller influence on the O-D and D-D partial radial distribution functions of heavy water than on the O-H and H-H ones of light water. After correcting for NQEs the O-H bondlengths in light and heavy water have become different: the O-D ones are about 0.5 % shorter than the O-H ones. Following NQE corrections, the total RDF of null water does show hydrogen related features at the position of the intramolecular O-H peak. Based on a cross-check procedure involving the NQE-corrected total and partial radial distribution functions, it can be stated that concerning the structure of liquid water, the assumption that H and D are equal is valid to a very good approximation for intermolecular correlations. These findings are also supported by our path integral molecular dynamics simulations.
