Vibrational frequencies and structural determination of cyanogen isocyanate

The vibrational frequencies and corresponding normal mode assignments of cyanogen isocyanate (NCNCO) are examined theoretically using the gaussian98 set of quantum chemistry codes. All normal modes were successfully assigned to one of seven types of motion predicted by a group theoretical analysis (CO stretch, C-N stretch, CN stretch, CN stretch, NCO bend, NC-N bend, and N-CN bend). Theoretical infrared and Raman intensities are reported. The molecular orbitals and bonding of cyanogen isocyanate are examined.