CH STRETCHING OVERTONE SPECTRA AND INTENSITIES OF VAPOR-PHASE NAPHTHALENE

Room temperature vapor phase CH stretching overtone spectra of naphtha lene are reported for the first time. The vibrational overtone spectra of naphthalene are recorded in the Delta v(CH) = 2 and 3 regions by c onventional near-infrared spectroscopy and in the Delta V-CH = 4 and 5 regions by intracavity titanium:sapphire laser photoacoustic spectros copy. Absolute oscillator strengths are obtained from the conventional spectra. The photoacoustic spectra provide relative oscillator streng ths between the observed peaks within a given overtone. Peaks correspo nding to two nonequivalent CH stretching local modes are consistently assigned. Oscillator strengths are calculated with an anharmonic oscil lator local mode model and ab initio dipole moment functions. We compa re the calculated and experimental oscillator strengths. Our simple ca lculations, which contain no adjustable parameters, are in very good a greement with the observed intensities.