MICROWAVE SPECTRA OF METHYL FORMATE ISOTOPOMER (HCOO$^{13}$CH$_3$)

Author Institution: Department of Physics, University of Toyama, 3190 Gofuku, Toyama, 930-8555 Japan; Kanazawa University, Japan; Department of Chemistry, University of Toyama, 3190 Gofuku, Toyama, 930-8555 JapanMethyl formate is a well-known interstellar molecule found in the star-forming region. One possible methyl formate production reaction is the reaction of methanol with other chemical species. Since the methyl rotor is originated from the methanol and $^{13}$CH$_3$OH has already been identified in space, it is quite likely to detect HCOO$^{13}$CH$_3$ in the near future. The microwave spectra of the methyl formate isotopomer (HCOO$^{13}$CH$_3$) could provide the rest frequencies as well as some indication about the production mechanism. We observed the microwave spectra of HCOO$^{13}$CH$_3$ by means of the FT-microwave spectrometer and the conventional source modulation spectrometer. The lines in the ground state were assigned and analyzed based on Hougen's tunneling matrix formulation