Structure and Analytical Potential Energy Function of the Ground State of HS Molecule

The dissociation energy,equilibrium geometry and harmonic frequency of the ground state X2Π of molecule HS are calculated with the density fungtional theory(B3P86,B3LYP)and two kinds of quadratic configuration-interaction methods(QCISD,QCISD(T))presented in Gaussian03 program package The reasonable dissociation limit for the state X2Π is derived.The whole potential energy curve for the state have a least-squares fit to the Murrell-Sorbie function.The spectroscopic data(Be,αe,ωe,and ωeχe) and the force constants(f2,f3 and f4) are calculated.It is gained that the Murrell-Sorbie function form is suitable state of molecule HS.Comparison of the theoretical determinations of dissociation energies,equilibrium interatomic distances and harmonic frequency shows that the present work is more complete and in better agreement with experiments than previous theories.