INVESTIGATION OF THE GROUND VIBRATIONAL-STATE OF CD3OH BY A NEW RITZ PROGRAM FOR DIRECT ENERGY-LEVEL FITTING

The complete absorption spectrum of CD3OH between 30 and 1200 cm-1 has been measured on the Bruker Fourier transform spectrometer of the Phy sical Chemistry Institute of the University of Giessen. In the present work we present the assignment of more than 20 000 lines between 30 a nd 850 cm-1, corresponding to transitions within the vibrational groun d state of the molecule. These assignments have been performed with th e help of a new computer program which evaluates the energies of the i nvolved levels by the Rydberg-Ritz combination principle and can tackl e such perturbations as Fermi-type resonances or Coriolis interactions . Up to now this program has evaluated the energies of 1789 levels bel onging to A-type symmetry and of 2417 levels belonging to E-type symme try, all in the vibrational ground state of the molecule. The evaluati on of the energy level values allows comparisons between different iso topic species. (C) 1994 Academic Press, Inc.