氢键对OH伸缩振动频率的影响

EFFECT OF HYDROGEN BOND ON THE OH STRETCHING VIBRATIONAL FREQUENCY

计算了水、甲醇和硅烷醇分子单体和相应二聚体的振动频率．分别采用二阶Mφller-Plesset微扰和密度泛函理论方法优化了分子的几何结构，计算了结合能和振动频率．分子的结合能计算考虑了基矢叠加误差校正．通过与实验结果比较评价了两种计算方法，研究了氢键相互作用对分子结构和OH伸缩振动频率的影响．结果表明，较强的氢键相互作用会引起较明显的结构变化，从而导致较大的振动频移．

It reports the vibrational frequency of the water, methanol and silanol monomers and the corresponding hydrogen bonded dimers employing quantum chemical calculations. The geometries of the systems are optimized by using second -order Mφller- Plesset perturbation theory and density functional theory respectively. The binding energy and vibrational frequency are calculated by these two methods. The basis set superposition error is considered for binding energy calculations. Compared with experimental results, these two methods are compared and the geometrical changes and OH stretching vibational frequency shift on formation of the hydrogen bonds are analyzed. It is shown that the stronger hydrogen bonding interaction will lead to considerable geometrical changes and larger frequency shift.