The Infrared Absorption Bands of Acetylene

Abstract

The present interpretations of the overtone bands in the infrared spectrum of acetylene are unsatisfactory in that they either do not fulfill the known selection rules or else fail to give satisfactory numerical agreement between calculated and observed band positions. A new arrangement of the complete infrared spectrum of acetylene is given which is in accord with the selection rules and yields consistent numerical results. Several of the anharmonic and interaction constants are thus determined for the five fundamental frequencies. It is remarked that there is probably a direct connection between the magnitudes of these anharmonic constants and the intensities of the overtone bands.