The Submillimeter Rotational Spectrum of Ethylene Glycol up to 890 GHz and Application to ALMA Band 10 Spectral Line Data of NGC 6334I

The rotational spectrum of the most stable conformer of ethylene glycol (HO­(CH2)2OH) has been recorded between 360–890 GHz using a frequency-modulation submillimeter spectrometer. The refinement and extension of the spectroscopic parameters over previous efforts provide predicted catalog frequencies for ethylene glycol with sufficient accuracy for comparison to high-frequency astronomical data. The improvement in the cataloged line positions, and the need for improved accuracy enabled by high-frequency laboratory work, is demonstrated by an analysis of ethylene glycol emission at 890 GHz in the high-mass star-forming region NGC 6334I in ALMA Band 10 observations. The need for accurate rotational spectra at submillimeter wavelengths/THz frequencies is discussed.