Toward a molecular orbital derived empirical potential for liquid simulations
Toward a molecular orbital derived empirical potential for liquid simulations
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DOI：
10.1021/jp962833a
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发表时间：
1997-01-23
影响因子：
3.3
通讯作者：
Gao, JL
中科院分区：
文献类型：
--
作者：
Gao, JL
提出了一种利用QM/MM混合技术和半经验波函数处理流体系统中多体极化效应的新方法。在这种方法中，每个溶剂分子的电子结构由一个反对称行列式波函数表示，该波函数可以在经典轨道的每一步通过完全收敛的变分QM计算来确定，或者可以与分子动力学模拟中的核坐标一起作为动态变量来处理。在确定分子波函数时，采用了QM/MM混合方法。这种分子轨道衍生的液体模拟经验势(模型)类似于Berne和他的同事介绍的波动电荷模型；然而，该模型势是一个量子化学模型，而不是FC模型中采用的纯经验电荷平衡方案。该方法还可推广应用于大分子体系的处理。以双分子络合物为例，说明了模型势描述双分子相互作用的能力。与从头计算结果的合理吻合表明，模型势可用于液体模拟的参数化。
A new method for the treatment of many-body polarization effects in fluid systems is presented, making use of hybrid QM/MM techniques and the semiempirical wave function. In this approach, the electronic structure of each solvent molecule is represented by an antisymmetric determinant wave function, which can be determined by fully converged variational QM calculations at each step of the classical trajectory or can be treated as dynamic variables along with the nuclear coordinates in molecular dynamics simulations. In determining the molecular wave functions, a hybrid QM/MM method is used. This molecular orbital derived empirical potential for liquid simulations (MODEL) is analogous to the fluctuating charge model introduced by Berne and co-workers; however, the MODEL potential is a quantum chemical model as opposed to a purely empirical charge equilibration scheme employed in the FC model. The method may also be extended for the treatment of large molecular systems. The capability of the MODEL potential for describing bimolecular interactions was illustrated for bimolecular complexes. Reasonable agreement with ab initio results suggests that the MODEL potential may be parametrized for liquid simulations.