The rovibronic energies of the SiNSi radical in its [formula omitted] electronic state

Abstract

We present the results of a calculation of the rovibronic energies of the SiNSi radical in its X ˜ 2 Π g electronic ground state. At bent geometries, the electronic degeneracy is split to give a lower state of A 2 symmetry and an upper state of B 2 symmetry; each state is linear at equilibrium. The rovibronic calculation involves consideration of the Renner effect, and we initially made the calculation using ab initio A 2 and B 2 potential surfaces. The term values obtained were of help in making vibronic assignments in a newly obtained spectrum of the molecule. Having vibronically assigned the spectrum, we refined the potentials in a fitting to the vibronic term value separations. The optimized potentials allow us, in principle, to predict all rovibronic energies of the X ˜ Π g 2 state.