Matrix isolation IR spectroscopic and ab initio studies of C3N- and related species

Coupled cluster calculations were carried out for C3N-, CCNC-, C3N, CCNC, C3N+, and C3O. They support the experimental identification of the C3N- ion by means of matrix isolation infrared (IR) spectroscopy. The anion was generated in electric discharges through the cyanoacetylene isotopomers HC3 N-14, (HC3N)-N-15, and (HC3N)-H-2, trapped in cryogenic rare gas matrices (Ne, Ar, Kr), and detected via its two most intense IR absorption bands, assigned to the nu(1) and nu(2) stretching vibrations. C3N- appears to be quite a stable anion, with a vertical detachment energy predicted to be as high as 4.42 eV. A large equilibrium electric dipole moment of 3.10 D facilitates the investigation of C3N- by microwave spectroscopy and radio astronomy. Various structural parameters and spectroscopic properties have been calculated for all tetra-atomic species considered. (c) 2008 American Institute of Physics.