Interfacing ab initio Quantum Mechanical Method with Classical Drude Osillator Polarizable Model for Molecular Dynamics Simulation of Chemical Reactions.
Interfacing ab initio Quantum Mechanical Method with Classical Drude Osillator Polarizable Model for Molecular Dynamics Simulation of Chemical Reactions.
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DOI：
10.1021/ct800116e
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发表时间：
2008-06
影响因子：
5.5
通讯作者：
Zhenyu Lu;Yingkai Zhang
中科院分区：
文献类型：
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作者：
Zhenyu Lu;Yingkai Zhang
为了进一步提高量子力学/分子力学（QM/MM）方法的精度和适用性，我们将量子力学/MM方法与经典的Drude振子极化MM力场（ai-QM/MM-Drude）相结合.不同的耦合方法已经采用和比较：1。传统的双自洽场（SCF）方法; 2.直接SCF方案，其中QM密度和MM Drude位置同时收敛; 3.微迭代SCF方案，其中极化模型的Drude位置在QM计算的每个自洽场（SCF）步骤期间完全收敛; 4.一步Drude更新方案，其中MM Drude位置仅更新一次，而不是在每个分子动力学（MD）步骤期间完全收敛。最后三个耦合方法被认为是有效的，并可以实现所需的收敛，在类似数量的QM SCF步骤相比，相应的QM方法耦合到一个非极化力场。通过采用伞采样方法对甲基氯-氯离子体系的甲基转移反应和水溶液中甘氨酸分子内质子转移反应进行Born-Oppenheimer分子动力学模拟，验证了ai-QM/MM-Drude方法的可行性和适用性.我们的结果表明，ai-QM/MM-Drude方法是非常有前途的，它提供了一个更好的描述QM/MM相互作用，同时可以达到相当的计算效率相比，相应的传统的从头算QM/MM方法.
In order to further improve the accuracy and applicability of combined quantum mechanical/molecular mechanical (QM/MM) methods, we have interfaced the ab initio QM method with the classical Drude oscillator polarizable MM force field (ai-QM/MM-Drude). Different coupling approaches have been employed and compared: 1. the conventional dual self-consistent-field (SCF) procedure; 2. the direct SCF scheme, in which QM densities and MM Drude positions are converged simultaneously; 3. the micro-iterative SCF scheme, in which the Drude positions of the polarizable model are fully converged during each self-consistent field (SCF) step of QM calculations; 4. the one-step-Drude-update scheme, in which the MM Drude positions are updated only once instead of fully converged during each molecular dynamics (MD) step. The last three coupling approaches are found to be efficient and can achieve the desired convergence in a similar number of QM SCF steps comparing with the corresponding QM method coupled to a non-polarizable force field. The feasibility and applicability of the implemented ai-QM/MM-Drude approach have been demonstrated by carrying out Born-Oppenheimer molecular dynamics simulations with the umbrella sampling method to determine potentials of mean force for both the methyl transfer reaction of the methyl chlorine-chlorine ion system and the glycine intra-molecular proton transfer reaction in aqueous solution. Our results indicate that the ai-QM/MM-Drude approach is very promising, which provides a better description of QM/MM interactions while can achieve quite similar computational efficiency in comparison with the corresponding conventional ab initio QM/MM method.