The first observation of the rhodium monofluoride molecule: Jet-cooled laser spectroscopic studies

Rhodium monofluoride has been observed and spectroscopically characterized. RhF molecules were produced under jet-cooled conditions in a laser vaporization molecular beam source by the reaction of a laser-vaporized rhodium plasma with SF6 doped in helium, and studied with laser-induced fluorescence spectroscopy under both medium and high resolution. More than 25 bands have been observed in laser-induced fluorescence between 18 500 and 24 500 cm-1 and five of these have been recorded at 200 MHz resolution. All bands of appreciable intensity have been rotationally analyzed. The ground electronic levels has Omega=2, which is attributed to an inverted (3)Pi state from the 2delta(4)6pi(3)12sigma(1) electron configuration. The ground level rotational constants are B=0.272 45 cm(-1), D=1.035x10(-7) cm(-1). Very small ground level Lambda doublings are evident in the spectrum. Excited states having Omega=1, 2, and 3 have been identified. Dispersed fluorescence spectroscopy from 11 excited levels has been used to locate a large number of low-lying vibronic states within the energy range up to 8000 cm-1. A ground state vibrational interval of similar to575 cm-1 is suggested. (C) 2004 American Institute of Physics.