N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, 119991 Moscow, Russia.
J Phys Chem A. 2010 Feb 11;114(5):2201-12. doi: 10.1021/jp908259p.
Quantum-chemical calculations of molecular complexes (NH(3))(3)Zn(2+)...(H(2)O)(n)...NH(3) (C(n), n = 11, 16, 21, and 30) simulating a proton wire donor-water chain-acceptor were carried out. Earlier found periodicity in the length of the O-H bonds in water chain is explained within the framework of a one-component harmonic model. In complexes C(n), the geometry and electronic structure of ionic defect in water chain with an excess proton were studied. Calculations carried out at ab initio (B3LYP/6-31+G**) and semiempirical (PM3) levels of theory predict different patterns of distribution of the O-H bonds lengths and positive charge on the H-bond hydrogen atoms in the region of ionic defect. The obtained data show how a length of water chain and position of a protonated water link in the chain influence the ionic defect structure. To describe the observed structures of ionic defect, the harmonic model was used and the role of parameters of the H-bonded chain was investigated. The performed analysis explains different mechanisms (concerted and stepwise) of proton transfer along the H-bonded chain derived from ab initio and semiempirical calculation schemes.
（NH(3))(3)Zn(2+)...(H(2)O)(n)...NH(3)（C(n），n = 11、16、21 和 30）模拟质子导线供体-水链-受体的分子配合物的量子化学计算已经完成。在单组分调和模型的框架内，解释了先前在水链中 O-H 键长度周期性发现的原因。在 C(n)中，研究了离子缺陷的几何形状和电子结构在水中链中带多余质子。在从头算（B3LYP/6-31+G**）和半经验（PM3）理论水平上进行的计算预测了离子缺陷区域中 O-H 键长度和氢键氢原子上正电荷的不同分布模式。所获得的数据表明水链的长度和质子化水链在链中的位置如何影响离子缺陷结构。为了描述观察到的离子缺陷结构，使用了调和模型并研究了氢键链参数的作用。所进行的分析解释了源自从头算和半经验计算方案的沿着氢键链的质子转移的不同机制（协同和逐步）。
