Mf. Arendt et al., EMISSION-SPECTROSCOPY OF THE PREDISSOCIATIVE EXCITED-STATE DYNAMICS OF ACROLEIN, ACRYLIC-ACID, AND ACRYLOYL CHLORIDE AT 199-NM, The Journal of chemical physics, 103(14), 1995, pp. 5877-5885
The emission spectroscopy of acrolein (C3H4O), acrylic acid (C2H3COOH)
, and acryloyl chloride (C2H3COCl) excited at 199 nm elucidates the do
minant electronic character of the excited state reached by the optica
l transition at this wavelength. Progressions in the C=C and C=O stret
ching overtones and various combination bands suggest the antibonding
orbital has mixed pi()(C=C)/pi(*)(C=O) character. We interpret the re
sults in conjunction with ab initio calculations at the configuration
interaction singles level to identify the influence of resonance in th
e excited state of these conjugated molecules. The results on acrylic
acid are of particular interest as excitation in this absorption band
produces the HOCO intermediate of the OH+CO-->H+CO2 reaction that is i
mportant in combustion. (C) 1995 American Institute of Physics.