HIGH-RESOLUTION FTIR AND PHOTOACOUSTIC OVERTONE SPECTRUM OF HCCL

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