Further Analysis of the Vinyl Iodide Microwave Spectrum

Publisher Website
Google Scholar
Abstract
Reanalysis of the published vinyl iodide microwave spectrum produced refined values of previously measured constants, and determined two quantities hitherto not known with precision: χ ab , the off‐diagonal quadrupole coupling constant, and Δ, the interial defect. This value of Δ agrees with one computed from the infrared spectrum by the approximate method of Herschbach and Laurie. The rotational constants are, neglecting centrifugal‐distortion effects, A = 53.3 ± 0.4 × 10 4 MHz , B = 3258.72 ± 0.03 MHz , C = 3066.66 ± 0.03 MHz , and Δ = 0.24 ± 0.08 amu·Å2. The quadrupole coupling constants are χ aa = − 1654.3 ± 1 MHz , χ bb = 768.8 ± 1 MHz , χ ab = −710 ± 25 MHz . Diagonalization of the χ tensor gives χ αα = − 1847 MHz and χ ββ = 962 MHz . The angle between the a axis and the C–I bond is 15.2° ± 0.7°, assuming the χ tensor diagonal along the C–I bond.