Self-broadening of the rotational Raman lines of O2, N2, CO2, and CO, and foreign-gas broadening of O2 and N2 by He and Ar were measured in the pressure range from 7 to 43 atm at room temperature. Spectrograms were obtained with Hg 2 537 Å as exciting line and a reciprocal linear dispersion of 11.2 cm−1 per mm. In each case the broadening was found to be proportional to the pressure so that a broadening coefficient [Formula: see text] could be defined. The broadening coefficient shows a monotonie decrease with increasing rotational quantum number J. The values of [Formula: see text] for N2 and their variation with J are in good agreement with the values calculated theoretically by Van Kranendonk on the basis of quadrupolar interaction in the impact approximation.

The Raman spectrum of benzene-d6 vapour was excited in a multiple reflection cell by an Ar+ laser and was photographed with a spectral slit width of ~0.15 cm−1. Extensive structure (164 maxima) was observed for the ν2 (C—C stretching) fundamental but only the S branch (39 maxima) of the ν1 (C—D stretching) band was well-resolved. These totally symmetric bands were analysed and molecular constants determined from a least-squares fit. Three doubly degenerate bands were observed; ν15 and ν16 were unresolved, and in ν17 only 19 lines could be measured. Consequently, no detailed analyses were possible but the values of some molecular constants were estimated.

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Hypersensitization by baking of various Kodak photographic emulsions is studied from the point of view of high-resolution Raman spectroscopy. In the 4400-4900-A region baking can increase the sensitivity of IIa-O plates to ~4 times that of 103a-O plates for long exposures. In the Raman region for Ar(+) laser excitation, 4700-5800 A, baked Ila-D plates show good sensitivity and low reciprocity failure. Baked IIIa-J plates have better resolving power than the IIa-D type, but the reciprocity failure is greater, and the useful region does not extend beyond 5300 A.

Spatially resolved gain measurements at 10.6 μm have been made transverse to the discharge in an axially flowing CO2 laser amplifier. The composition of the amplifier medium has been varied to include initially pure CO2, binary mixtures of CO2:CO, CO2:He, and CO2:N2, and triple mixtures of CO2:N2:He. Strong spatial variations of gain are observed which depend on the gas mixture, flow rate, temperature, pressure, and current. Corresponding spatial intensity profiles of the sidelight emission of CO2 at 4.3 μm are shown.