Molecular level approaches for investigation of electron transfer in nonpolar solvents.
Molecular level approaches for investigation of electron transfer in nonpolar solvents.
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研究非极性溶剂中电子转移的分子水平方法。
DOI：
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发表时间：
2007
影响因子：
4.4
通讯作者：
M. Tachiya
中科院分区：
文献类型：
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作者：
I. Leontyev;M. Tachiya
这两位作者扩展了他们之前发表在Leontyev和TchiyaJ上的工作。化学。太棒了。123,224502(2005年)，并研究了在非极性溶剂正己烷中芘和二甲基苯胺之间的正向电子转移和反向电子转移。采用了前人工作中采用的分布函数方法和分子动力学技术。提出了在线性响应近似下求重组能和溶剂化自由能差的两种算法(I和II)。这两种算法与不同的截断方案相结合，并在可极化和不可极化的溶剂模型中进行了测试。只有在使用粒子网格Ewald处理的模拟中，两种算法所获得的结果之间才达到一致。结果表明，算法I为计算重组能和溶剂化自由能差提供了一个可靠的方案。此外，我们还提出了一种新的算法，称为G-函数算法，该算法不假定线性响应近似，并在计算溶剂化自由能差上进行了测试。G函数算法的结果与算法I和算法II的结果之间的一致性相当好，尽管这取决于模拟的统计一致性程度。在非极性溶剂的情况下，G函数方法具有实际意义，因为与传统的热力学积分方法不同，它只需要对体系的初态和终态进行平衡的分子构型系综。
The authors extend their previous work published in Leontyev and TachiyaJ. Chem. Phys. 123, 224502 (2005) and study not only forward but also reverse electron transfer between pyrene and dimethylaniline in a nonpolar solvent, n-hexane. The distribution function methodology and molecular dynamics technique adopted in their previous work are used. Two algorithms (I and II) are formulated for obtaining the reorganization energy and the solvation free energy difference in the linear response approximation. The two algorithms are combined with different cutoff schemes and tested for polarizable and nonpolarizable solvent models. Agreement between the results obtained by the two algorithms was achieved only for simulations employing the particle mesh Ewald treatment. It is concluded that algorithm I provides a reliable scheme for evaluation of the reorganization energy and the solvation free energy difference. Moreover, a new algorithm referred to as the G-function algorithm is formulated which does not assume the linear response approximation, and is tested on evaluation of the solvation free energy difference. Agreement between the results from the G-function algorithm and those from algorithms I and II is fairly good, although it depends on the degree of statistical consistency of the simulations. In the case of nonpolar solvents the G-function method has practical importance because, unlike the conventional thermodynamic integration approach, it requires equilibrium molecular configuration ensembles only for the initial and final states of the system.