Difference frequency laser spectroscopy of HCNH +: Observation of the isotopic species and the hot bands

Abstract

The infrared spectra of the isotopic species of HCNH +, HCND + and H 13CNH +, have been observed with a difference frequency laser system. The r s structure of the ion has been determined by combining the rotational constants of the normal species and DCNH + previously obtained. Two hot bands of the normal species, presumably ν 1 + ν 4 ← ν 4 and ν 1 + ν 5 ← ν 5, have also been observed and the spectroscopic constants have been determined.