Predissociations in the 0u+ and 1g States of K2

Published

October 1, 2002

Author(s)

T Bergeman, Paul S. Julienne, Carl J. Williams, Eite Tiesinga, M R. Manaa, H Wang, P L. Gould, W C. Stwalley

Abstract

Recently Wang, Gould and Stwalley showed by exciting atomic fragments that predissociation occurs in the Ig and O⁺_u states of K2. In this study, we supplement the interpretation given in the original report with a more detaileddiscussion. The calculations presented here use discrete variable representation (DVR), close coupling, and semiclassical methods, and incorporate an ab initio calculation of diagonal and off-diagonal spin-orbit elements. The predicted predissociation widths for the I_g state are too narrow to be observed directly, but may be correlated with the strength of the spectral lines observed by exciting atomic fragments. The mising Ņ=90 level of the 1g state in the observed fragmentation spectrum, where the predissociation rate is calculated to be nearly maximum, is attriibuted to a node in the absorption line strength close to this vibrational level. Since the available information on K2 electronic states (despite recent progress) gives inadequate information on the inner walls of the A state and especially of the b state, calculations of predissociation in the O⁺/_u state can give only a range of possible widths. We fit widths to O⁺/_u spectral lines observed by monitoring trap loss. The fitted experimental widths aresignificantly larger than the maximum calculated predissociation widths, suggesting that there was line broadening associated with the laser power required for the observation.

Citation

Journal of Chemical Physics

Volume

117

Issue

No. 16

Pub Type

Journals

Keywords

photoassociation spectroscopy, potassium dimer, predissociation, spin-orbit interactions, ultra-cold collisions

Citation

Bergeman, T. , Julienne, P. , Williams, C. , Tiesinga, E. , Manaa, M. , Wang, H. , Gould, P. and Stwalley, W. (2002), Predissociations in the 0_u⁺ and 1_g States of K₂, Journal of Chemical Physics (Accessed May 9, 2024)