Tunneling motion and wave-function symmetry

Sergey P. Belov, Institute of Applied Physics of Russian Academy of Sciences

Abstract: Results of an experimental study of the nuclear spin and coordinate wave-function symmetry of symmetric ( HI:HI, HBr:HBr) and nonsymmetric (H79Br:H81Br, Ar:HBr) dimers, based on relative intensity measurements of well resolved quadrupole structure components of Ro and P1 tunneling-rotation transitions will be presented. Nuclear spin statistics, nuclear spin selection rules, nuclear spin wave-function mixing, ?I = 2 and ?I = 1 spin “forbidden”transitions as well as qualitative and quantitative changes in high resolution spectra of dimers due to energy nonequivalence of their two equilibrium configurations and/or due to the permutation symmetry violation will be discussed. The results of this study are important for the molecular symmetry theory development and enable one to understand better a deep relation between permutation of identical particles and potential surface symmetry.