O_2分子基态X~3Σ_g~-分析势能函数

Analytical Potential Energy Function of the Ground State (X~3Σ_g~-) of O_2 Molecule

摘要: 利用原子分子反应静力学的有关原理,推导出了O2分子的合理离解极限;使用CID、B3LYP、QCISD和QCISD(T)等理论方法,在D95(d),6-311G和6-311G*基组下,对O2分子基态的平衡结构和谐振频率进行了优化计算,得出了QCISD(T)方法为最优方法、6-311G*为最优基组的结论.利用QCISD(T)/6-311G*对O2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成了Murrell-Sorb ie势能函数.由拟合得到的势能函数,计算与X3Σg-态相应的光谱常数(Be,αe,ωe和ωeeχ),其结果与实验值符合得较好.

Abstract: The reasonable dissoliation limits for O2 are determined based on the atomic and molecular reaction statics;the energy equilibrium geometry and harmonic frequency of the ground state X3Σ-g are calculated using the methods of CID,B3LYP,QCISD and QCISD(T) with the basis sets of D95(d),6-311G and 6-311G*.It is gained that the basis set 6-311G* is the most suitable for the energy calculation of O2 molecule.The whole potential curves for the ground state is scanned using QCISDC(T)/6-311G*,then fit to Murrell-Sor...