Photodissociation spectroscopy of Ca+-CO2

Electronic spectra are observed for the metal cation complex Ca+-CO2, using resonance-enhanced photodissociation spectroscopy. The complexes are produced in a laser vaporization/supersonic expansion source, size selected and excited on resonance, and the mass-analyzed product is measured in a time-of-flight mass spectrometer. Both Ca+ and CaO+ dissociation channels are observed to have sharp resonances. Spectra from two isotopomers, the Ca-40(+) and Ca-44(+) species, are recorded and analyzed. Transitions from the X(2) Sigma(+)(v ''=0) ground vibronic state to several vibrational levels in the D (IIr)-I-2 excited electronic state are measured. The structure of the complex is confirmed to be linear by the presence of prominent spin-orbit multiplets. Spectroscopic constants for the Ca-40(+)-CO2 complex are determined: v(00) = 22099.1 cm(-1), A(so)' = 136.3 cm(-1), omega(e)' = 258.9 cm(-1), and omega(e)x(e)' = 4.23 cm(-1). (C) 1996 American Institute of Physics.