High-Resolution FTIR and Photoacoustic Overtone Spectrum of HCCI

The first and second C-H overtone vibration-rotation absorption spectra of monoiodoacetylene (HCCI) have been recorded using an FTIR spectrometer with an instrument resolution of about 0.005 cm-1 (0.9/MOPD). The third overtone spectrum has been obtained using a titanium:sapphire ring laser spectrometer with a spectral resolution of about 0.02 cm-1. Due to anharmonic resonances like Fermi and Darling-Dennison resonances, accompanying bands can be observed close to the main overtone band. All the observed bands have been rotationally analyzed. Published vibrational data together with present results are used in a model which includes anharmonic resonances. Vibrational assignments of the observed bands are based on this calculation. The agreement between calculated and observed energy levels is good considering the amount of data available. Copyright 1997 Academic Press. Copyright 1997Academic Press