ANALYSIS OF THE STIMULATED RAMAN SPECTRUM OF THE $\nu_{16}/\nu_{2}+\nu_{18}$ FERMI DIAD OF BENZENE
Loading...
Date
1985
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
The Raman spectrum of benzene was measured with the aid of the ionization-detected stimulated Raman $technique^{1}$ in the region $1580 - 1625 cm^{-1}$ containing the $v_{16} E_{2g}$ fundamental band and the $\nu_{2} +\nu_{18} E_{2g}$ combination band enhanced by close Fermi resonance with the fundamental. With the $^{-}$-$0.007 cm^{-1}$ resolution attained, the strong $^{\circ} D$ and $^{s}$sS branch lines were completely resolved for the higher K values. Both bands have the regular structure of $\Delta K = \pm 2, \Delta 1 = \pm 1$ transitions, but the lower frequency band exhibits a perturbation localized near K = 21, which was ascribed to a $J_{x,y^{-}}$ Coriolis interaction with the $\nu_{7} +\nu_{18} E_{1g}$ state. A Hamiltonian matrix containing the three states and their Fermi, Coriolis, and l-type interactions was used for the treatment of the upper states of the observed bands yielding a set of spectroscopic constants which reproduce the observed spectrum with an over-all standard deviation of $0.0025 cm^{-1}$. The unperturbed origins of the $\nu$16 and $\nu-2+\nu_{18}$ states are at 1600.966 and $1599.881 cm^{-1}$ respectively : the identity of the lower lying state as $\nu_{2}+\nu_{18}$ was established by its constant $C\zeta = +0.05498 cm^{-1}$ which is very close to the value reported in the literature for $\nu_{18}$.
Description
$^{1}$ P. Esherick and A. Owyoung, Chem. Phys. Letters 103, 235 (1983).
Author Institution: Sandia National Laboratories; Sandia National Laboratories; Department of Physics, Pennsylvania State University
Author Institution: Sandia National Laboratories; Sandia National Laboratories; Department of Physics, Pennsylvania State University