BF分子第一激发三重态的势能函数与光谱常数

摘要

the possible electronic states and their reasonable dissociation limits of the first excited state for BF are determined based on the atomic and molecular reaction statics. The equilibrium geometry, the harmonic frequency and the dissociation energy about the first excited state( A3∏ )have been accurately calculated using the methods as QCISD and QCISD (T) at the basis sets of 6 - 311 G (3df,3pd), 6 - 311 + + G ( 3 df, 3pd ) and cc - PVQZ. After scanning the whole potential curve for the first excited state by using QCISD (T)/6 -311 G( 3df,3pd), then have a least square fitted to Murrell - Sorbic function. At last , the spectroscopy constants ( Be, αe,we, and wexe ) are cal- culated according to the M -S function, which are in good agreement with the experimental data.%利用原子分子反应静力学原理,推导出了BF分子第一激发三重态的合理离解极限;使用QCISD和QCISD（T）方法,在6-311G（3df,3pd）、6-311＋＋G（3df,3pd）和cc-PVQZ基组下,对BF分子第一激发三重态的平衡结构、谐振频率和离解能进行了优化计算,应用QCISD（T）/6-311G（3df,3pd）对BF分子第一激发三重态进行了单点能扫描,并将扫描结果用最小二乘法拟合Murrell-Sorbie势能函数.由拟合得到的势能函数,计算了与第一激发三重态（A3∏）相应的光谱常数（Be、αe、ωe和ωeχe）,计算结果与实验符合得很好.