THE B(2)SIGMA(+)[-X(2)SIGMA(+) TRANSITION OF HGI

The B2∑+ ← X2∑+ fluorescence excitation spectrum of HgI between 367 and 322 nm is presented. The radicals were produced and rotationally cooled in a corona-excited supersonic expansion. Spectral analysis of the isotopomer fine structure has shown that transitions from the lowest ground state levels excite a wide range of high vibrational levels in the B ion-pair potential. (vB = 30-70). Excited state molecular constants are reported which are valid between vB = 0 and 70. A new B-state equilibrium bondlength has been obtained from Franck-Condon calculations which reproduce the hot-band intensities in the excitation spectra. New Franek-Condon factors were derived for 25 ≥ vB ≥ 0 and 20 ≥ vX ≥ 0 which are expected to be of use in the interpretation of the HgI B → X laser output near 440 nm. © 1993 Academic Press, Inc.