IcMRCI+Q Study of the Spectroscopic Properties of the 14 ?-S and 49 ? States of the SiN- Anion in the Gas Phase.

ABSTRACT: This paper calculates the potential energy curves of the 14 ?-S and 49 ? states, which come from the first three dissociation channels of the SiN- anion. These calculations are conducted using the valence internally contracted multireference configuration interaction and the Davidson correction approach. Core-valence correlation and scalar relativistic corrections are taken into account. The potential energies are extrapolated to the complete basis set limit. The spin-orbit coupling is computed using the state interaction approach with the Breit-Pauli Hamiltonian. We found that the X¹?? (?'' = 0-23) and a³?? (?' = 0-2) states of SiN- are stable at the computed adiabatic electron affinity value of 23,262.27 cm-1 for SiN. Based on the calculated potential energy curves, the spectroscopic parameters and vibrational levels were determined for all stable and metastable ?-S and ? states. The computed adiabatic electron affinity of SiN and the spectroscopic constants of SiN- (X¹??) are all in agreement with the available experimental data. The d³??, 2???, 1??, and 1??- quasi-bound states caused by avoided crossings were found. Calculations of the transition dipole moment of a³??? to X¹??0+ are shown. Franck-Condon factors, Einstein coefficients, and radiative lifetimes of the transition from the a³??? (?' = 0-2) to the X¹??0+ state are evaluated.

SUBMITTER: Xing W 

PROVIDER: S-EPMC6017747 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature