Three-dimensional ab initio dipole moment surfaces and stretching vibrational band intensities of the XH3 molecules  

作　　者：刘安雯 胡水明 丁昀 朱清时 

机构地区：[1]Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China

出　　处：《Chinese Physics B》2005年第10期1946-1953,共8页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China （Grant Nos 20103007 and 20473079）.

摘　　要：Stretching vibrational band intensities of XH3 （X=N, Sb） molecules are investigated employing three-dimensional dipole moment surfaces combined with the local mode Hamiltonian model. The dipole moment surfaces of NH3 and SbH3 are calculated with the density functional theory and at the correlated MP2 level, respectively. The calculated band intensities are in good agreement with the available experimental data. The contribution to the band intensities from the different terms in the polynomial expansion of the dipole moments of four group V hydrides （NH3, PH3, AsH3 and SbH3） are discussed. It is concluded that the breakdown of the bond dipole approximation must be considered. The intensity “borrowing” effect due to the wave function mixing among the stretching vibrational states is found to be less significant for the molecules that reach the local mode limit.Stretching vibrational band intensities of XH3 （X=N, Sb） molecules are investigated employing three-dimensional dipole moment surfaces combined with the local mode Hamiltonian model. The dipole moment surfaces of NH3 and SbH3 are calculated with the density functional theory and at the correlated MP2 level, respectively. The calculated band intensities are in good agreement with the available experimental data. The contribution to the band intensities from the different terms in the polynomial expansion of the dipole moments of four group V hydrides （NH3, PH3, AsH3 and SbH3） are discussed. It is concluded that the breakdown of the bond dipole approximation must be considered. The intensity “borrowing” effect due to the wave function mixing among the stretching vibrational states is found to be less significant for the molecules that reach the local mode limit.

关 键 词：OVERTONE dipole moment infrared band intensity local mode 

分 类 号：O434.3[机械工程—光学工程]