Ab initio study of CnO, CnO+ and CnHO+ species

Abstract

Calculations on C₃O and C₂O, their positive ions and their protonated forms at levels of theory up to MP4SDQ/6-311G**//MP2/6-31G** and also using the G1 procedure are reported. Harmonic vibrational frequencies at the HF/6-31G* level of theory are reported. Ionisation potentials and proton affinities of the neutral species were calculated. Values of the dipole moments and rotational constants of the neutral species and their positive ions are given. Protonation at C(1) is preferred by both species. The dissociation energy of C_nO to CO and C or C₂(n= 2, 3) was calculated.