CALCULATED MICROWAVE AND INFRARED SPECTRA OF ATMOSPHERIC AND INTERSTELLAR ASYMMETRIC MOLECULES FROM MICROWAVE LABORATORY MEASUREMENTS

Abstract

The microwave spectra of the following light asymmetric tops have been studied in the range 10 GHz up to 500 GHz: $H_{2}O, SO_{2}, O_{3}, H_{2}CO$, HCOOH and most of their isotopic species. The present study concerns the pure rotational spectra of the molecules in their ground vibrational states and in the lower energy excited states. Using the Watson Hamiltonian, a least-squares process yields molecular constants and their statistical errors. We have available a program which allows the systematic calculation of frequencies, uncertainties and relative intensities of pure rotational or vibrrotational lines. Some examples of these calculated spectra for $SO_{2}$ and $O_{3}$ will be presented and compared with observed spectra.