The High-Resolution Infrared Spectrum of the v5 Band of Deuterated Formic Acid (DCOOH)

Abstract

The Fourier transform infrared spectrum of the v5 band of deuterated formic acid (DCOOH) has been measured with a resolution of 0.004 cm-1 in the frequency range of 1090-1180 cm-1. Using a Watson's A-reduced Hamiltonian in the Ir representation, a total of 1731 assigned unperturbed transitions have been analyzed to provide rovibrational constants for the upper state (v5 = 1) with a standard deviation of 0.000363 cm-1. The band is A type with an unperturbed band center at 1142.31075 ± 0.00002 cm-1. The band is expected to be perturbed by a nearby v4 band through a Fermi resonance term and possibly a Coriolis term. The resonance is particularly noticeable for Ka = 10, and 11, at high J values. About 215 perturbed lines were identified but they were not included in the final fit. © 1998 Academic Press.