Infrared Photodissociation Spectroscopy of Ti⁺(CO₂)₂Ar and Ti⁺(CO₂)_n(n=3-7) Comple xes (cited: 1)

Ti⁺(CO₂)₂Ar and Ti⁺(CO₂)_n(n=3-7) complexes are produced by laser vaporization in a pulsed supersonic expansion. The ion complexes of interest are each mass-selected in a time-of-flight spectrometer, and studied with infrared photodissociation spectroscopy. For each complex, a sharp band in the CO stretching frequency region is observed, which confirms the formation of the OTi⁺CO(CO₂)_n-1 oxide-carbonyl species. Small OTi⁺CO(CO₂)_n-1 complexes (n≦5) exhibit CO stretching and antisymmetric CO₂ stretching vibrational bands that are blue-shifted from those of free CO and CO₂. The experimental observations indicate that the coordination number of CO and CO₂ molecules around TiO⁺ is five. Evidence is also observed for the presence of another electrostatic bonding Ti⁺(CO₂)₂ structural isomer for the Ti⁺(CO₂)₂Ar complex, which is characterized to have a bent OCO-Ti⁺-OCO structure stabilized by argon coordination