skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Characterization of the first excited [sup 1][Pi][sub 1] and the ground [ital X] [sup 1][Sigma][sup +] states of MgXe. I. Analysis of the [sup 1][Pi][sub 1][l arrow][ital X] [sup 1][Sigma][sup +] bound--bound transitions

Journal Article · · Journal of Chemical Physics; (United States)
DOI:https://doi.org/10.1063/1.465482· OSTI ID:5574169
 [1];  [2];  [3]
  1. Department of Chemistry, St. Patrick's College, Maynooth, Co. Kildare (Ireland)
  2. Los Alamos National Laboratory, Group CLS-4, M/S J567, Los Alamos, New Mexico 87545 (United States)
  3. Department of Chemistry, University of Utah, Salt Lake City, Utah 84112 (United States)

Laser induced fluorescence (LIF) excitation spectra recorded for the vibrational bands in the Mg(3[ital s]3[ital p] [sup 1][ital P][sub 1])[center dot]Xe([sup 1][Pi][sub 1])[l arrow]Mg(3[ital s]3[ital s] [sup 1][ital S][sub 0])[center dot]Xe ([ital X] [sup 1][Sigma][sup +]) system have been analyzed, yielding absolute vibrational assignments and values of [omega][sub [ital e]x[ital e]]=1.585[plus minus]0.02 and [omega][sub [ital e]]=97.5[plus minus]1.0 cm[sup [minus]1] for the [sup 1][Pi][sub 1] state of [sup 24]Mg[sup 132]Xe. From a Birge--Sponer extrapolation, the well depth of this state is estimated to be 1500 cm[sup [minus]1]. Simulations of rotationally structured spectra of three of the most intense vibrational bands are consistent with [ital R][sup [double prime]][sub [ital e]]=4.56[plus minus]0.12 A for the [ital X] [sup 1][Sigma][sup +] state. From Morse function extrapolation of the excited state rotational constants from the simulations, and Franck--Condon intensity simulations of the [sup 1][Pi][sub 1][l arrow][ital X] [sup 1][Sigma][sup +] vibrational progressions, [ital R][sup [prime]][sub [ital e]] for the [sup 1][Pi][sub 1] state is estimated to be 3.07[plus minus]0.10 A. The [sup 1][Pi][sub 1] state of MgXe fluoresces strongly. The corresponding [sup 1][Pi][sub 1] states of ZnXe and CdXe do not fluoresce, but action'' spectra from the production (via predissociation) of metal atom [sup 3][ital P][sub [ital J]] states are observed. Possible reasons for these differences are discussed in terms of spin--orbit induced predissociation. It is concluded that predissociation of the MgXe([sup 1][Pi][sub 1]) state is not observed because the crossing between the repulsive [sup 3][summation][sup +][sub 1] and the attractive [sup 1][Pi][sub 1] potential curves does not occur until energies higher than those accessible experimentally.

OSTI ID:
5574169
Journal Information:
Journal of Chemical Physics; (United States), Vol. 99:12; ISSN 0021-9606
Country of Publication:
United States
Language:
English