The Fluorescence Excitation Spectrum of HCO B2A'-X2A', 000 Band

Abstract The rotationally resolved laser-induced fluorescence spectrum of the HCO B 2A′– X 2A′ transition in the 000band is observed under thermalized conditions. The formyl radical is produced from acetaldehyde photolyzed at wavelengths 310 or 308 nm. Some spin-splittings of the spectra are resolved. About 988 transitions toKa′≤ 3 andN′ ≤ 24, ∼94% of the observed lines, are assigned in this work including weak ΔKa= ±2 transitions that become allowed because of the effects of axis-switching.

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