Al(H2O)63+水交换反应溶剂效应的量子化学团簇模型-密度泛函理论方法研究

在气相模型、极化连续模型、超分子模型和超分子-极化连续模型的基础上,采用量子化学团簇模型密度泛函理论方法,在B3LYP/6-311+G(d,p)基组水平下系统地开展了以下研究:优化得到Al(H2O)63+水交换反应的反应物、过渡态和产物构型,采用MP2方法在相同基组水平下计算得到相应的单点能,考虑零点振动能、热力学校正项和熵等参数的影响,计算得到Al(H2O)63+水交换反应的Gibbs自由能变和反应速率常数kex.计算结果表明:GP-SM//MP2-PCM和GP-SM-PCM//MP2-PCM模型得到的kex相近,并且与文献值相符,说明GP-SM//MP2-PCM模型可以充分考虑真实溶剂效应和主体溶剂效应,适用于Al(H3O)63+体系水交换反应的模拟.

Investigation of the Solvent Effects for the Water-Exchange Reactions of Al(H2O)63+ by Quantum Chemical Cluster Models-Density Functional Theory Method

Based on the four models (gas phase (GP),polarizable continuum model (GP-PCM),supermolecule model(GP-SM) and supermolecule-polarizable continuum model (GP-SM-PCM)),we systematically conducted the following investigations using quantum chemical cluster models-density functional theory method.The water-exchange reaction of Al(H2O)63+ was simulated at the level of B3LYP/6-311+-G(d,p),and the single-point energies were calculated using MP2 method.Taking zero-point energies,thermal corrections and entropies into consideration,the activation Gibbs energy barries and water-exchange rate constant(kex) were calculated.The logkex values for water-exchange reactions of Al(H2O)63+ with GP-SM//MP2-PCM and GP-SM-PCM//MP2-PCM models were similar and consistent with available literature values.This indicates that the GP-SM//MP2-PCM model could simulate the water-exchange reaction of Al(H2O)63+ satisfactorily.