Pang Weixiu, Wang Meishan, Yang Chuanlu, Zhang Yongfeng
School of Physics and Electronic Engineering, Ludong University, Yantai 264025, China.
J Chem Phys. 2007 May 21;126(19):194301. doi: 10.1063/1.2733654.
The equilibrium structure, spectroscopy constants, and anharmonic force field of germanium dichloride have been calculated at MP2, B3LYP, and CCSD(T) levels of theory employing two basis sets, cc-pVDZ and cc-pVTZ, respectively. The computed geometries, rotational constants, and vibration-rotation interaction constants, and quartic centrifugal distortion constants are compared with the available experimental data. The harmonic frequencies, anharmonic constants, and cubic and quartic force constants are predicted. The calculated results show that the MP2 results are in excellent agreement with experiment and represent a substantial improvement over the results obtained from B3LYP. The CCSD(T) method is also an advisable choice to study anharmonic force field of molecules.
采用cc-pVDZ和cc-pVTZ这两种基组，分别在MP2、B3LYP和CCSD(T)理论水平下计算了二氯化锗的平衡结构、光谱常数和非谐力场。将计算得到的几何结构、转动常数、振动-转动相互作用常数和四次离心畸变常数与现有的实验数据进行了比较。预测了谐波频率、非谐常数以及三次和四次力常数。计算结果表明，MP2的结果与实验结果非常吻合，并且相对于B3LYP得到的结果有显著改进。CCSD(T)方法也是研究分子非谐力场的一个可取选择。
