The optical-optical double resonance (OODR) spectra of Rydberg 3Σ+ states of Hg(n3S1)Ne (n=8-10) and Hg(83S1)Ar were measured by using A and B states as intermediate states in the OODR process. The interatomic potentials of three states of HgNe and one state of HgAr were determined over a wide range of interatomic distance, R=3-7 Å, by the analysis of the vibrational structure of their OODR spectra. It was found that the potential shape varies sensitively with n and converges to that of the ion core, HgNe+. Dissociation energies (De) of the Rydberg states for the n=8, 9, and 10 were derived to be 209(2), 284(2), and 309(2) cm-1, respectively. Using the quantum defect orbital [G. Simons, J. Chem. Phys. 60, 645 (1974)], which represents a hydrogenic radial wave function for a Rydberg state with a given quantum defect, was introduced to interpret the characteristic n dependence of the interatomic potential. It was shown that the interatomic potential for the Rydberg states can be expressed by the sum of the ion core potential, Vion(R), and the repulsive potential, Vex(R), which originates mainly from the exchange repulsion between the Rydberg electron and the attached rare gas atom. The interatomic potential for Hg(8 3S1)Ar, whose dissociation energy [De=1602(4) cm-1] is much deeper than that of Hg(83S1)Ne, was also interpreted consistently by expressing the potential as V ion(R) + Vex(R).
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry