The rotational spectrum of deuterated nitric acid

The terahertz rotational spectrum of many small fundamental gas-phase molecules provides an absolutely specific spectral fingerprint and insight into the intramolecular forces through the fitted rotational and vibrational constants. We are currently assigning and fitting the measured rotational transitions in several of the lowest lying, thermally populated, vibrational states of deuterated nitric acid. We will describe the general characteristics of the spectrum and compare the rotational and centrifugal distortion constants of each state to those of the normal species.