The Predissociation Mechanism for2Σ+Rydberg States of CaCl (original) (raw)

Abstract

This work summarizes experimental results from recent ion-dip spectroscopy studies of CaCl and from previously unpublished optical-optical double-resonance work with specific regard to predissociation processes of 2 ⌺ ϩ Rydberg states in the low n* (n* ϭ 7, IP Ϫ E n* ϭ 2240 cm Ϫ1 ) region. A single repulsive state (assigned as 2 ⌺ ϩ ) was found to be responsible for all observed predissociations of 2 ⌺ ϩ Rydberg states. The n*-dependent internuclear distances of the intersections between Rydberg states and the repulsive 2 ⌺ ϩ state were determined through the use of trial-and-error Franck-Condon calculations. Values of energy-descaled electronic matrix elements governing the Rydberg 7 repulsive state interaction were obtained from the measured linewidths (0.6 Ͻ ⌫ Ͻ 1.2 cm Ϫ1 ) and computed Franck-Condon densities.

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