Knowledge Bank

Ab initio configuration interaction calculations are reported on the Low-lying electronic states of HgCl and HgBr. The calculations employ a relativistic effective core $potential1$ on Hg and nonrelativistic effective core $potentials2$ on chlorine and bromine. Emission energies and spectroscopic constants for the $B2\Sigma 1/2+\to X2\Sigma 1/2+$ lasing transition are compared to experiment. Spin-orbit coupling effects are included using a simple, effective, one-electron spin-orbit operator. The production of electronically excited HgCl and HgBr by photodissociation of $HgCl2$ and $HgBr2$ will be considered briefly.