Mg+CO2 ion-molecule complexes are produced in a pulsed supersonic nozzle cluster source. These weakly bound complexes are mass-selected and studied with laser photodissociation spectroscopy in a reflectron time-of-flight mass spectrometer system. An electronic transition assigned as 2Π←X 2Σ+ is observed with an origin at 29625 cm-1 (vac). The spectrum is characterized by a six-member progression in the metal-CO2 stretching mode with a frequency (ω′e) of 381.8 cm-1. An extrapolation of this progression fixes the excited state dissociation energy (D′0) at 11194 cm-1. The corresponding ground state value (D″0) is 5150 cm-1 (14.7 kcal/mol). The 2Π 1 2, 3 2 spin-orbit splitting is 56 cm-1. These studies were guided by ab initio calculations by Bauschlicher and co-workers, which provide accurate predictions of the electronic transition energy, vibrational constants and dissociation energy.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry