Vibrational spectra and force constants of symmetric tops: Rovibrational analysis of 2 ν_{6} and 2 ν_{6}  ν_{6} of H _{3}Si ^{35}Cl and H _{3}Si ^{37}Cl, and a new method for the determination of A_{0} and D_{K}^{0}
Abstract
The gasphase ir spectra of monoisotopic H _{3}Si ^{35}Cl [35] and H _{3}Si ^{37}Cl [37] in the 2 ν_{6} region near 1300 cm ^{1} have been studied with a resolution of 0.05 cm ^{1}. A total of 467 and 1206 lines have been assigned for [35] and [37], respectively, and analyzed by a leastsquares procedure, σ( J, K) ∼ 6 × 10 ^{3}cm ^{1}, to yield three parameters for the 2 ν_{6}^{0} and six for the 2 ν_{6}^{±2} states for both isotopomers. In the ν_{6} region {32}/{47} and {127}/{150} lines have been assigned to the hot bands 2 ν_{6}^{0}  ν_{6}^{±1} and 2 ν_{6}^{±2}  ν_{6}^{±1} of [35] and [37], respectively. While a hot band 2 ν_{t}^{0}  ν_{t}^{±1} does not provide any information above that available from ν_{t}^{±1} and 2 ν_{t}^{0}, a hot band 2 ν_{t}^{±2}  ν_{t}^{±1} may supply extra data concerning the ground state. A new method for the evaluation of A_{0} and D_{K}^{0} from combination differences of ν_{t}^{±1}, 2 ν_{t}^{±2}, and 2 ν_{t}^{±2}  ν_{t}^{±1} of a symmetric top with C_{3 v} symmetry is presented. Application to [35] and [37] yielded A_{0} of 2.8447(5) and 2.8437(3) cm ^{1}, and D_{K}^{0} of 2.12(20) and 2.38(9) × 10 ^{5} cm ^{1}, respectively.
 Publication:

Journal of Molecular Spectroscopy
 Pub Date:
 August 1984
 DOI:
 10.1016/00222852(84)901656
 Bibcode:
 1984JMoSp.106..349B