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An important component of the Extragalactic Distance Database is a group of catalogs related to the measurement of H i line profile parameters. One of these is the All Digital H i catalog which contains an amalgam of information from new data and old. The new data result from observations with Arecibo and Parkes Telescopes and with the Green Bank Telescope, including continuing input since the award of the NRAO Cosmic Flows Large Program. The old data have been collected from archives, wherever available, particularly the Cornell University Digital H i Archive, the Nançay Telescope extragalactic H i archive, and the Australia Telescope H i archive. The catalog currently contains information on ∼15,000 profiles relating to ∼13,000 galaxies. The channel-flux per channel files, from whatever source, is carried through a common pipeline. The derived parameter of greatest interest is W m50 , the profile width at 50% of the mean flux. After appropriate adjustment, the parameter W mx is derived, the line width that statistically approximates the peak-to-peak maximum rotation velocity before correction for inclination, 2V max sini.

Infra-red spectra between 4000 and 40cm-I are reported for EtOH and EtOD suspended in argon matrices at 20 K. The small bandwidths in the low-temperature matrix reveal the presence of bands due to both trans and gauche conformers, and a complete vibrational assignment for the more stable trans conformer is made. The ratio of trans to gauche conformers in the vapour phase at room temperature is estimated to be 2 : 1. Concentration studies result in the identification of open chain dimer, trimer and tetramer, and cyclic tetramer, species from their OH stretching vibrations. The effect of association on other regions of the spectrum is examined.Two conformers of the ethanol molecule may exist, with the OH group trans (I) or gauche (11) with respect to the methyl group :The monomer OH stretching frequency in solution has been reported by some authors as displaying a~ymmetry,l-~ while others report that the band is ~ymmetrical.~ A detailed study of 12 isotopic species from 4000 to 400 cm-l in vapour, liquid and solid phases as well as in solution was inconclusive, the authors tentatively suggesting that the molecule is essentially in the gauche form, on the basis that strong interaction occurs between modes which would be of different symmetry for the trans conformer. However, Michielsen-Effinger reports, from microwave studies, the existence of both trans and gauche conformers of ethanol in the vapour phase, the trans form being the more stable. Takano, Sasada and Satoh6 confirm the existence of a gauche conformer, from similar studies.

Infrared spectra are reported of a strongly hydrogen-bonded complex between ammonia and hydrogen chloride trapped in argon and nitrogen matrices. There are substantial differences between the spectra of the complex in the two matrices, and these are attributed to increased proton transfer from hydrogen chloride to ammonia in the more polar nitrogen matrix. The corresponding gas-phase complex would be expected to display less proton transfer than the complex in an argon matrix.