INDUCTION OF OPTICAL-TRANSITIONS THROUGH COMPLEXATION WITHIN HG RARE-GAS VAN-DER-WAALS SYSTEMS

The high repulsive states of HgAr and HgNe van der Waals complexes, co rrelating with Hg 6s6d atomic states have been investigated by double resonance spectroscopy, through the first excited state A (3)0(+) and B (3)1 of the complexes. The repulsive potentials have been fitted thr ough numerical Franck-Condon simulations. They have been characterized by perturbative calculation as quasi-pure 6d Sigma potentials in Hund 's case a. The strong Hg-rare gas electrostatic interaction potential overruns the spin-orbit interaction at distances shorter than 7 Angstr om. These observed repulsive states are mostly of Omega=1 character co rrelating with D-3(3) at infinite distances. The contribution from the potential of Omega=0(-) symmetry correlating with D-1(2) is of minor importance. Therefore, the absorption in the repulsive states of the c omplex arises mostly from proximity induced absorption in an optically forbidden transition P-3(1)-->D-3(3). A perturbative model accounts w ell for the bound free absorption intensities experimentally observed. (C) 1995 American Institute of Physics.