PREDISSOCIATION DYNAMICS OF THE A(2)SIGMA(+) STATE OF SH AND SD

The technique of cavity ring-down spectroscopy has been used to invest igate predissociation in the A (2) Sigma(+) state of the SH and SD rad icals. Spectra were recorded of the A-X (1,0) band of SH and the (1,0) , (2,0) bands of SD. Linewidth measurements of transitions to individu al rovibrational levels of the A state revealed increasing predissocia tion rates with vibrational and rotational quantum number. These and a ll other available data have been reproduced, quantitatively, by Fermi Golden Rule calculations employing the best (experimentally determine d) analytic potential for the A state and ab initio repulsive potentia ls and spin-orbit coupling matrix elements. (C) 1997 American Institut e of Physics.