Interaction between CO₂ and NbO₂⁺: Infrared photodissociation spectroscopic and theoretical study

The mass-selected infrared photodissociation (IRPD) spectroscopy combined with quantum chemical calculations was utilized to study the interactions between niobium dioxide cation and carbon dioxide molecules. Experimental and calculated results indicate that the CO2 molecules are weakly bound to the NbO2+ cation in an end-on configuration via a charge-quadrupole electrostatic interaction. For n >= 6, CO2 molecules in the second shell no longer have contribution to CO2 activation. The similarity of experimental spectra for n >= 7 also indicates that ion cores of NbO2+(CO2) n cluster have not changed. Compared with the congeneric YO+ complexes (Phys. Chem. Chem. Phys., 2018, 20, 19314-19320), NbO2+ is found to be thermodynamically and kinetically more difficult to react with CO2.