Highly excited vibrational levels studies using time-resolved Fourier transform emission spectroscopy

The spectroscopy and dynamics of highly excited vibrational levels of the a1A1 and b1B1 states of CH2 were studied using time-resolved Fourier transform emission spectroscopy. The use of a Fourier transform spectrometer allows efficient acquisition of dispersed fluorescence spectra over several thousand cm-1 range in the visible, with better than 1 cm-1 resolution, from this short lived and low concentration species. Furthermore, the temporal evolution of the dispersed fluorescence spectra due to collisional relaxation can be monitored with 50 ns time-resolution. The results presented and discussed in this paper are: (1) the state-to-state rotational energy transfer and reactive cross- sections for b1B1 (0, 16O, 0) CH2; and (2) rotational analysis of several previously unobserved high vibrational levels of the CH2 a1A1 state.