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High Resolution Infrared Spectra of the Ņ2 Ņ3, Ņ4, and 2Ņ3 Bands of 32S16O3



A G. Maki, Thomas A. Blake, R L. Sams, N Vulpanovici, J Barber, E T. Chrysostom, Tony Masiello, J Nibler, A Weber


New measurements are reported for the infrared spectrum of sulfur trioxide, 32S16O3, with resolution ranging from 0.0015 cm-1 to 0.0025 cm-1. Rovibrational constants have been measured for the fundamentals Ņ2, Ņ3, and Ņ4, and the overtone band 2Ņ3. Comparisons are made with the earlier high-resolution measurements on SO3, and the high correlation among some of the constants related to the Coriolis coupling of the Ņ2 and Ņ4 levels is discussed in order to understand the areas of disagreement with the earlier work. Splittings of some of the levels are observed and the splitting constant for K = 3 of the ground state is determined for the first time. Other observed splittings include the K = 1 levels of 2Ņ3(l=2), the K=2 levels of Ņ3, and Ņ4, and the K = 3 levels of Ņ2. The analysis shows that there are level crossings between the l = 0 and l=2 states of 2Ņ3 that allow one to determine the separation of the sub-band centers for these two states even though access to the l=0 state from the ground state is electric-dipole forbidden. This is a generalized phenomenon that should be found for many other molecules with the same symmetry. The l-type resonance constant that couples the l=0 and 2 states is roughly the same in magnitude as q3 which causes the splitting of the l=1 levels of the Ņ3 fundamental.
Journal of Molecular Spectroscopy
No. 2


high resolution, infrared, spectroscopy, spectrum, sulfur trioxide


Maki, A. , Blake, T. , Sams, R. , Vulpanovici, N. , Barber, J. , Chrysostom, E. , Masiello, T. , Nibler, J. and Weber, A. (2001), High Resolution Infrared Spectra of the &#325;<sub>2</sub> &#325;<sub>3</sub>, &#325;<sub>4</sub>, and 2&#325;<sub>3</sub> Bands of <sup>32</sup>S<sup>16</sup>O<sub>3</sub>, Journal of Molecular Spectroscopy (Accessed October 2, 2023)
Created December 1, 2001, Updated February 17, 2017