Laser excitation and photoionization spectroscopy of the AO+ and B1 states of indium monoiodide: Ground state dissociation energy and photodissociation yield of In(6s 2S1/2)

Abstract

The dissociation energy of the InI ground state (X 1Σ+(O+)) and the relative yield of In(6s 2S1/2) from the photodissociation of InI by sequential two-photon absorption have been measured by laser-induced fluorescence and excitation spectroscopy in the 390–431 nm region. Laser excitation spectroscopy and photoionization experiments demonstrate that the XO+ dissociation energy is 25 340±90 cm−1, which agrees with the value suggested by Vempati and Jones [J. Mol. Spectrosc. 127, 232 (1988)] if the InI ground state is covalent. Seven previously unreported vibrational bands of the InI(B←X) transition have been observed and the molecular emission spectra indicate that the B 3Π1(1) state is predissociated above v=6. Splitting between the fine structure levels of the In np 2P1/2,3/2 (15⩽n⩽17) states has also been measured by fluorescence suppression spectroscopy, following the three photon excitation of InI in the 450–470 nm interval.