Theoretical study of spectroscopic constants and transition properties of silicon hydride cation

Autor: You Yu, Yun-Guang Zhang, Ge Dou, Jie Cui
Rok vydání: 2018
Předmět:
Zdroj: Journal of Molecular Structure. 1165:318-325
ISSN: 0022-2860
DOI: 10.1016/j.molstruc.2018.03.111
Popis: The potential energy curves and dipole moments for the lowest seven Λ − S states correlating to three dissociation limits Si + ( P 2 u ) + H ( S g 2 ) , Si + ( P g 4 ) + H ( S g 2 ) , and Si ( D g 1 ) + H + ( S g 1 ) of SiH+ cation are computed using multi-reference configuration interaction plus Davidson corrections method with the AWCV5Z-DK basis set. By solving the radical Schrodinger equation, the spectroscopic parameters of these states are obtained, which are in excellent agreement with available experimental values. The spin-orbit coupling effect is taken into account in the computations via the Breit-Pauli Hamiltonian operator, which causes the seven Λ − S states to split into fifteen Ω states. It is the first time that the spin-orbit coupling calculation is carried out on SiH+. The spin-orbit coupling leads to avoided crossing between B 1 Δ 2 and d Π 2 3 states, c 3 Σ 1 − and b Σ 1 + 3 states, respectively. The B 1 Δ 2 state has a double-well potential resulting from the avoided crossing. The potential energy curves and spectroscopic constants of the Ω electronic states are also depicted with the aid of the avoided crossing between electronic states of the same symmetry. In addition, the transition dipole moments, Franck-Condon factors and the radiative lifetimes for the X Σ 1 ↔ A Π 1 , A Π 1 ↔ B Δ 1 , a Π 3 ↔ d Π 3 , a Π 3 ↔ c Σ − 3 , c Σ − 3 ↔ d Π 3 , X Σ 0 + + 1 ↔ a Π 0 + 3 , and X Σ 0 + + 1 ↔ a Π 1 3 transitions are obtained.
Databáze: OpenAIRE
Externí odkaz: