BH分子基态的分析势能函数与光谱常数

Spectroscopic Parameters and Analytical Potential Energy Function for Ground State of BH Molecules

利用原子分子反应静力学的有关原理,推导出了BH分子的合理离解极限;采用QCISD理论方法,在6-311G(3df,3pd),6-311G(3df,2pd),6-311++G(3df,2pd)和cc-PVQZ基组下,对BH分子基态的平衡几何、离解能和谐振频率进行了优化计算,并利用QCISD/6-311++G(3df,2pd)对BH分子的基态进行了单点能量扫描,并将扫描结果用正规方程组拟合Murrell-Sorbie势能函数.由拟合得到的势能函数,计算与基态(X1Σ+)相应的光谱常数(βe,αe,ωe和ωeχe),其结果与实验符合得较好.

The possible electronic states and their reasonable dissociation limits for BH are determined based on the atomic and molecular reaction statics.The dissociation energy,equilibrium geometry and harmonic frequency of the ground state X1Σ＋ are calculated.Using QCISD theory at the basis sets of 6-311G（3df,3pd）,6-311G（3df,2pd）,6-311＋＋G（3df,2pd） and cc-PVQZ,the whole potential curve for the ground state are scanned using QCISD/6-311＋＋G（3df,2pd）,then have a least square fitted to Murrell-Sorbie function,and the last spectroscopy constants（βe,αe,ωe,and ωeχe） are calculated,which are in good agreement with the experimental data.