A High-Resolution Fourier Transform Infrared Study of the ν3, ν4, and ν5 Bands of Deuterated Formyl Chloride (DCOCl)

Abstract High-resolution infrared spectra of the low-lying ν 3 , ν 4 , and ν 5 fundamentals of the transient molecule DCOCl are reported. These type- A / B hybrid bands have been analyzed in detail, providing extensive rotational assignments for the DCO 35 Cl and DCO 37 Cl isotopomers. The ground state constants have been refined by a simultaneous fit of the available microwave data and FTIR combination differences from the three bands. The excited state constants have been determined by fitting assignments over a wide range of J and K a values. A small perturbation was found at high K a values in the ν 4 band and determined to be due to a Δ K a = −2 interaction with the rotational levels of the 6 1 vibrational state.