Dispersed fluorescence spectroscopy of jet-cooled FeCl2: A determination of ground-state vibrational parameters

Iron dichloride, FeCl2, has been produced at low rotational and vibrational temperatures in the gas phase using a supersonic expansion. Laser-induced fluorescence from several vibronic bands in the 288 nm band system has been dispersed to reveal extensive vibrational progressions. The symmetric stretching wavenumber, ν1 is determined to be 352.39(13) cm−1 for Fe35Cl2 in the ground electronic state. The antisymmetric stretching wavenumber, ν3 is found to be approximately 511 cm−1. The evidence suggests that the molecule is linear in both the ground and excited electronic states.