Theoretical Study On The Structure And Spectroscopy Of Two Hydride Ions

Many sulfur-containing molecules have been observed in interstellar space,they are of importance due to their chemical activity and relatively high abundance.From an astrophysical perspective,these molecules and ions are also of interest.SH molecule,the simplest sulfur-containing molecule,which is one of the most studied molecules at present.As a chemical intermediate,it will play an major role in many industrial processes,such as fossil fuel combustion and atmospheric sulfur cycle.This molecule is important in combustion and is considered to be an important intermediate product in the combustion of sulfur-containing molecules.Recently observed in interstellar media that sulfur-containing molecular SH and SH+,facilitate the formation of other sulfur-containing molecules,information on SH+is important for studying the chemical composition of the astrophysical environment.The group-IV monohydride ions are of importance because of their special properties in astrophysics,combustion processes and plasma chemistry.In this paper,the ab initio calculations is used to theoretically study the spectroscopic properties and transition properties of states of SH+and SnH+ions.(1)CCSD(T)and MRCI-F12 methods in combination with correlation consistent Gaussian basis set are adopted to study the PECs of X3?-and A3? state for SH+ion.The effects of Davidson modification,CV and SR correction are taken into account in this work.The SH+ion ground state X3?-and A3? state have obvious characteristics of multireference configuration.The present study provides a reference for further precise studies of structural and spectral information on SH+ion.(2)Using the MRCI-F12 method to calculate the spectroscopic properties and structure of SH+.The three dissociation limits of SH+correspond to 12 ?-S electronic states.The 12 A-S states split into 25? states The transition properties of SH+are given in this paper.The radiation lifetimes are agree well with the experimental results.At last,the SOC induced predissociation mechanisms of the A3? state have been discussed.(3)The MRCI method is used to calculate the electronic states of SnH+ion.The six dissociation limits of SnH+ion split into twelve dissociation limits,and the 21?-S states split into 47? states after considering the SOC effect.In addition,the Franck-Condon factor,transition dipole moment are also computed,the radiative lifetimes of a3?0+-X1?+0+,a3?1-X1?+0+ and A1?1-X1?+0+ transitions are also predicted.