The rotational spectrum of chlorine nitrate (ClONO2):: The ν5/ν6ν9 dyad

Chlorine nitrate is a molecule of both spectroscopic and atmospheric interest. It is a species whose spectrum in the infrared is marginally resolved in the Doppler limit, thereby limiting the spectroscopic study of its dense rovibrational structure. Analyses of its pure rotational spectrum in the millimeter and submillitneter (mm/submm) spectral regions of the ground, v(9), 2v(q), v(7), 3v(q), and v(7)v(9) vibrational states have been previously reported. In this paper, we report the recording of a new 'complete' mm/submm spectrum from 78 to 378 GHz using phase-lock and FASSST (FAst Scan Submillimeter Spectroscopic Technique) systems. We also report the use of these new data for redetermination of spectroscopic constants for the ground state and for an analysis of the v(5)/v(6)v(9) interacting dyad, whose corresponding infrared spectrum lies near 560 cm(-1). The simulation of the rotational structure of v(5) from the nim/submin analysis is of particular interest because it is one of the bands that is used for atmospheric remote sensing. (c) 2007 Published by Elsevier Inc.