Quantum mechanical/quantum mechanical methods. I. A divide and conquer strategy for solving the Schrodinger equation for large molecular systems using a composite density functional-semiempirical Hamiltonian
Quantum mechanical/quantum mechanical methods. I. A divide and conquer strategy for solving the Schrodinger equation for large molecular systems using a composite density functional-semiempirical Hamiltonian
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DOI：
10.1063/1.1290608
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发表时间：
2000-10-08
影响因子：
4.4
通讯作者：
Merz, KM
中科院分区：
文献类型：
--
作者：
Gogonea, V;Westerhoff, LM;Merz, KM
在此我们描述一种新的量子力学/量子力学（QM/QM）组合方法，用于求解大分子体系的薛定谔方程。这种新方法采用分而治之（D&C）策略将大分子体系划分为子体系，并使用复合密度泛函理论（DFT） - 半经验（SEM）哈密顿量来描述分子间相互作用。DFT和SEM子体系通过化学势耦合，并通过交换电子电荷达到平衡。对双原子、三原子和多原子分子分别使用DFT、SEM以及复合（DFT/SEM）方法进行的计算表明，当远离QM/QM边界区域时，马利肯电荷收敛到使用“纯”哈密顿量会得到的值。换句话说，我们发现每个SEM和DFT波函数的质量在很大程度上得以保留，这有力地表明这种方法可用于研究化学反应性，其方式与目前使用的量子力学/分子力学（QM/MM）组合方法非常相似。（C）2000美国物理学会。[S0021 - 9606(00)30438 - X]
Herein we describe a new combined quantum mechanical/quantum mechanical (QM/QM) method for solving the Schrodinger equation for large molecular systems. The new method uses the divide and conquer (D&C) strategy to partition a large molecular system into subsystems and a composite density functional theory (DFT)-semiempirical (SEM) Hamiltonian to describe the molecular interactions. The DFT and SEM subsystems are coupled through the chemical potential and are equilibrated by exchanging electronic charge. Calculations performed with the DFT, SEM, and composite (DFT/SEM) methods on diatomic, triatomic, and polyatomic molecules show that as one moves away from the QM/QM boundary region the Mulliken charges converge to the values that would be obtained using the "pure" Hamiltonian. In other words, we find that the quality of each SEM and DFT wave function is largely conserved, which strongly suggests that this type of approach could be applied to study chemical reactivity much in the same way combined quantum mechanical/molecular mechanical (QM/MM) methods are presently utilized. (C) 2000 American Institute of Physics. [S0021-9606(00)30438-X].