【摘要】 本文运用群论及原子分子反应静力学方法,推导了AlH分子的基态(X1Σ+)、第一激发态(A1Π)及第三激发态(C1S+)的电子态及相应的离解极限。并使用SAC/SAC-CI方法,采用D95(d)、6 311g(d)和cc PVTZ等基组对AlH分子的基态(X1Σ+)、第一激发态(A1Π)和第三激发态(C1S+)的平衡结构和谐振频率进行了几何优化计算。通过对三个基组的计算结果与实验结果的比较,得到cc PVTZ基组是三个基组中最优基组的结论。使用cc PVTZ基组,对AlH分子的基态(X1Σ+)、第一激发态(A1Π)和第三激发态(C1S+)进行了单点能扫描计算,并给出了AlH的基态(X1Σ+)、第一激发态(A1Π)和第三激发态(C1S+)的Murrell Sorbie函数形式的电子态的完整势能函数,进而得到了AlH分子第一激发态(A1Π)的激发能较小的结论。更多还原

【Abstract】 In this paper, the electronic states of the ground state (X()~1Σ~+), the first excited state (A()~1Π) and the third excited state (C()~1S~+) and their dissociation limit of AlH are correctly determined based on group theory and atomic and molecular reaction statics. The energies, equilibrium geometries and harmonic frequencies of the three electronic states of AlH have been calculated using the GSUM(Group Sum of Operators) method of SAC/SAC-CI with the basis sets D95, 6-311g and cc-PTVZ. Comparing the result from the above-mentioned three basis sets, the basis set cc-PVTZ is the best suitable for the energy calculation of AlH. The three potential curves for the three electronic states are further scanned using the SAC/cc-PVTZ method for the ground state and the SAC-CI/cc-PVTZ methods for the excited states, then have a least square fitted to Murrell-Sorbie function. The calculation was gained that the excited energy for the first excited state (A()~Π) is very small.更多还原