The association spectra of a number of acids and alcohols in the region λλ9000–11,000 have been observed both in solution and in the pure liquids. In each case a broad band with maximum near λ10,000 was observed while in the alcohols an additional weaker band near λ9000 appears to be present. Evidence is presented that the λ10,000 band is to be identified with the O–H group. This evidence includes the behavior of the association band with change in concentration and temperature and its presence in several substances in which absorption other than that due to the O–H group is practically absent in the region studied. New evidence is given that a weak intermolecular hydrogen bond is formed between acetone and methyl alcohol. It is pointed out that the presence of absorption in the narrow O–H bands is not to be taken as evidence of the absence of hydrogen bonds in case the absorption is weak. The character of the O–H absorption in the case of intermolecular hydrogen bonds is discussed and the probable nature of the spectrum in the case of an intramolecular bond is indicated. A relation between the energy of the hydrogen bond and the shift of the O–H vibrational frequency is pointed out and its use is suggested in the interpretation of certain spectra.

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A mixture of gases roughly simulating the primitive terrestrial atmosphere has been subjected to shock heating followed by a rapid thermal quench. Under strictly homogeneous conditions there is a very high efficiency of 5 x 10(10) molecules per erg of shock-injected energy for production of alpha-amino acids. Calculations suggest that rapid quenching bypasses the usual thermochemical barrier. The product of energy flux and efficiency implies the unexpected conclusion that shocks occurring on atmospheric entry of cometary meteors and micrometeorites and from thunder may have been the principal energy sources for pre-biological organic synthesis on the primitive earth.

The decomposition of nitromethane was studied over the temperature range 1000−1100 K in reflected shock waves. CH3NO2 and the reaction products were analyzed by gas chromatography. The derived gross rate constant and activation energy for the disappearance of CH3NO2 is consistent with that of Glänzer and Troe. A reaction mechanism consisting of 99 chemical reactions was developed to simulate the experimental data of the present study and that of Hsu and Lin. Good agreement between experiments and simulations was achieved. It appears that significant amounts of CH3NO2 are destroyed through secondary reactions that involved highly reactive free radicals (H, OH, and CH3), suggesting the need for redeterming the true unimolecular decay rate constant for CH3NO2. For improvement of the performance of the model, several other rate constants also need to be determined. The final section is a preliminary report on a spectrophotometric technique for measuring the loss of nitromethane due to pyrolysis by recording its absorption of UV radiation, directed axially along a small diameter shock tube. Although only semiquantitative data were obtained, this novel procedure merits discussion.

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