Analysis of High-Resolution Infrared and Ņ1 CARS Spectra of 34S18O3
Tony Masiello, J Barber, E T. Chrysostom, J Nibler, A G. Maki, A Weber, Thomas A. Blake, R L. Sams
Three fundamental modes and several hot bands of 34S18O3 have been investigated using both infrared spectroscopy and coherent anti-Stokes Raman scattering spectroscopy (CARS). Coriolis coupling effects are particularly noticeable in 34S18O3 due to the close proximity of the Ņ2 and Ņ4 fundamental vibrations, whose wave number values are 477.508 64(5) and 502.055 65(4) cm-1. The uncertainties in the last digits are shown in parentheses and are two standard deviations. Hot band transitions from Ņ2, Ņ4 levels give access to infrared inactive Ņ2, Ņ4 combination/overtone levels which interact strongly with levels of the Raman-active Ņ1 symmetric stretching mode due to indirect Coriolis couplings, l-resonances, and Fermi resonances. The result is a complex Ņ1 CARS Q-branch spectrum that is the most perturbed of the four SO3 isotopomers we have studied. The relative importance of these interaction terms on the Ņ1 CARS spectrum is examined in some detail and accurate rovibrational sonstants are deteremined for all of the mixed states, leading to deperturbed values of 1004.662(24), 0.000 350 3(9), and 0.000 706 6(12) cm-1 for Ņ1, α1B, and α1C, respectively. The Be value is found to be 0.310 817(12) cm-1, which gives an equilibrium bond length re of 141.7339(3) pm, in excellent agreement with values of 141.7340(1) and 141.7347(7) pm reported earlier for 32S16O3 and 34S16O3.
Journal of Molecular Spectroscopy
CARS spectroscopy, high resolution, infrared, isotopomer, sulfur trioxide
, Barber, J.
, Chrysostom, E.
, Nibler, J.
, Maki, A.
, Weber, A.
, Blake, T.
and Sams, R.
Analysis of High-Resolution Infrared and Ņ<sub>1</sub> CARS Spectra of <sup>34</sup>S<sup>18</sup>O<sub>3</sub>, Journal of Molecular Spectroscopy
(Accessed December 1, 2023)