Center for Biological and Engineering Sciences, Sandia National Laboratories, Albuquerque, New Mexico 87185, USA.
Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, USA.
J Chem Phys. 2017 Oct 28;147(16):161728. doi: 10.1063/1.4986244.
We use ab initio molecular dynamics (AIMD) calculations and quasi-chemical theory (QCT) to study the inner-shell structure of F(aq) and to evaluate that single-ion free energy under standard conditions. Following the "no split occupancies" rule, QCT calculations yield a free energy value of -101 kcal/mol under these conditions, in encouraging agreement with tabulated values (-111 kcal/mol). The AIMD calculations served only to guide the definition of an effective inner-shell constraint. QCT naturally includes quantum mechanical effects that can be concerning in more primitive calculations, including electronic polarizability and induction, electron density transfer, electron correlation, molecular/atomic cooperative interactions generally, molecular flexibility, and zero-point motion. No direct assessment of the contribution of dispersion contributions to the internal energies has been attempted here, however. We anticipate that other aqueous halide ions might be treated successfully with QCT, provided that the structure of the underlying statistical mechanical theory is absorbed, i.e., that the "no split occupancies" rule is recognized.
我们使用从头算分子动力学（AIMD）计算和准化学理论（QCT）来研究 F(aq) 的内壳层结构，并评估标准条件下的单离子自由能。根据“不分裂占据”规则，在这些条件下，QCT 计算得出的自由能值为-101 kcal/mol，与表列值（-111 kcal/mol）非常吻合。AIMD 计算仅用于指导有效内壳层约束的定义。QCT 自然包含量子力学效应，这些效应在更原始的计算中可能会引起关注，包括电子极化率和感应、电子密度转移、电子相关、分子/原子协同相互作用通常、分子柔韧性和零点运动。然而，这里没有尝试直接评估色散对内部能量的贡献。我们预计，只要吸收了基础统计力学理论的结构，即承认“不分裂占据”规则，QCT 就可以成功地处理其他水合卤化物离子。
