THE HIGH-RESOLUTION LASER-INDUCED FLUORESCENCE EXCITATION SPECTRUM OF FREE JET COOLED TOLUENE

Abstract

The laser-induced fluorescence excitation spectrum of toluene was obtained using a free jet, expansion $apparatus^{1}$ and a resolution of $\sim .05 cm^{-1}$. An analysis of the rotational features in this spectrum has been made using a free internal rotor-asymmetric top hamiltonian contour calculation. The results show that the effective rotational temperature of the torsionless ground electronic state is $-1K^{\circ}$. The analysis further suggests that all torsional levels are not cooled to this same extent. The limits of the free internal rotor-asymmetric top model developed are discussed in terms of computed and measured rovibronic spectral features.