BCl分子X^1Σ^+,a^3Π和A^1Π态的光谱性质  

Spectroscopic properties of BCl(X^1Σ^+, a^3Π, A^1Π)molecule

作　　者：刘慧[1] 邢伟[1] 施德恒[2] 孙金锋[2] 朱遵略[2] 

机构地区：[1]信阳师范学院物理电子工程学院,信阳464000 [2]河南师范大学物理与信息工程学院,新乡453007

出　　处：《物理学报》2014年第12期138-146,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61077073);河南省科技计划(批准号:142300410201);河南省教育厅科技计划重点项目(批准号:14B140023)资助的课题~~

摘　　要：采用Davidson修正的内收缩多参考组态相互作用方法(MRCI+Q)及Dunning等的相关一致基aug-ccpV6Z计算了BCl分子X1Σ+,a3Π和A1Π态的势能曲线.利用总能量外推公式,将这3个态的总能量分别外推至完全基组极限.对势能曲线进行核价相关修正及相对论修正计算,得到了同时考虑这两种修正的外推势能曲线.拟合势能曲线得到了3个态的主要光谱常数Te,Re,ωe,ωexe,Be,αe和De等,它们与已有的实验结果较为一致.利用获得的势能曲线,通过求解双原子分子核运动的径向Schrdinger方程,找到了BCl分子X1Σ+,a3Π和A1Π态的全部振动态,并得到了相应的振动能级和惯性转动常数等分子常数.还计算了a3Π—X1Σ+和A1Π—X1Σ+的跃迁偶极矩、Franck-Condon因子,预测了若干跃迁的辐射寿命.The X1Σ＋, a3Πand A1Πstates of BCl molecule are studied using the highly accurate valence internally contracted multireference configuration interaction approach including the Davidson modification. The Dunning’s correlation-consistent basis sets, aug-cc-pV6Z and aug-cc-pV5Z, are used in the study. To obtain more reliable results, the potential energy curves （PECs） of three electronic states are extrapolated to the complete basis set limit by the two-point total-energy extrapolation scheme. The effects of the core-valence correlation and relativistic corrections on the PECs are taken into account. By fitting these PECs, the spectroscopic parameters （Te , Re , ωe , ωe x e , B e , αe and D e ） of the X1Σ＋, a3Π and A1Π states of BCl are determined. These parameter values coincide with the experimental results. In addition, the whole vibrational states for X1Σ＋, a3Πand A1Πstates at J =0 （J is the rotational quantum number） are determined by numerically solving the radical Schr？dinger equation of the nuclear motion of diatomic molecules. For each vibrational state, the vibrational level and inertial rotation constants are obtained, which are in excellent accordance with the experimental results. With the potential energy curves obtained at MRCI＋Q/56＋CV＋DK level and the MRCI wave functions, the Franck-Condon factors, radiative lifetime of transition from a3Π and A1Π to the ground state are computed.

关 键 词：势能曲线 光谱常数 分子常数 辐射寿命 

分 类 号：O561.3[理学—原子与分子物理]