Gas-phase CH-Overtone band spectra of methyl acetate and ethyl acetate via incoherent broad-band cavity-enhanced absorption spectroscopy

Gas-phase overtone bands of methyl acetate and ethyl acetate were detected for up to v = 6-0 by incoherent broad-band cavity-enhanced absorption spectroscopy. The signal-to-noise ratios of v = 4-0 were achieved to be 40-50 by the 100 s integration time, suggesting an application possibility of this spectroscopic technique for environmental monitoring. Profiles of the observed overtone bands were analyzed in detail with the aid of theoretical calculations and their remarkable peaks were assigned to the progressions starting from the sym-metric CH-stretching bands. The harmonic frequencies, the anharmonicities, and the dissociation energies were derived.

Automated summary

In this study, gas-phase overtone bands of methyl acetate and ethyl acetate were detected using incoherent broad-band cavity-enhanced absorption spectroscopy. The observed overtone bands were analyzed with theoretical calculations to determine their peaks and related parameters.