Speaker
Dr
Ronald Lees
(Centre for Laser, Atomic and Molecular Sciences, Department of Physics, University of NB)
Description
Structure from high torsional levels of the CD$_3$OH isotopologue of methanol has been analyzed in Fourier transform spectra recorded at the Far-Infrared beamline of the Canadian Light Source synchrotron in Saskatoon. Energy term values for $A$ and $E$ torsional species of the third excited torsional state, v$_t$ = 3, are now almost complete up to rotational levels $K$ = 15, and thirteen substates have so far been identified for v$_t$ = 4. The spectra show interesting close groupings of strong high-v$_t$ sub-bands related by Dennison’s torsional symmetry index $/tau$, rather than $A$ and $E$, that can be understood in terms of a simple and universal free-rotor “spectral predictor” chart. The energy curves for the v$_t$ = 3 and 4 ground-state torsional levels pass through several of the excited vibrational states, and a number of anharmonic and Coriolis interactions have been detected through perturbations to the spectra and appearance of forbidden sub-bands due to strong mixing and intensity borrowing.
Primary author
Dr
Ronald Lees
(Centre for Laser, Atomic and Molecular Sciences, Department of Physics, University of NB)
Co-authors
Dr
Brant Billinghurst
(Canadian Light Source Inc.)
Dr
Li-Hong Xu
(Centre for Laser, Atomic and Molecular Sciences (CLAMS), Department of Physics, University of NB)
