HOF分子非谐性力场、光谱常数和振动能级的迭代三激发耦合簇计算

The study of anharmonic force fields,spectroscopic constants and vibrational levels of HOF using iterative triplet couple cluster approach

采用包含迭代三激发的耦合簇理论(CC3和CCSDT-3),在aug-cc-p VTZ基组水平上对HOF分子几何构型进行优化.通过解析二阶导数结合有限差分技术获得HOF二阶、完全三阶和半对角四阶力场.通过非谐性分析,得到其基频、旋振相互作用常数、非谐性常数和离心畸变光谱常数.应用二阶振动微扰理论(VPT2)得到HOF多个泛频峰位置.目前计算值与实验及其它文献结果符合良好.

The molecular equilibrium structure of HOF has been optimized using iterative triplet coupled cluster approach( CC3 and CCSDT-3) together with aug-cc-p VTZ basis set. Quadratic,full cubic and semidiagonal part of the quartic force field have been obtained by the analytic second derivatives and finite difference techniques.Fundamental frequencies,vibration- rotation interaction constants,anharmonic constants and centrifugal distortion constants have been evaluated according to the anharmonic analytics. Several overtones have been expected by the vibrational second-order perturbation theory( VPT2). The present calculation values are in good agreement with others theoretical and experimental results.