Absolute Intensities in the Hydrogen-Chloride Rotation Spectrum

Abstract

The development of new quantum theories which purport to furnish a means for the prediction of the absolute intensities of spectral lines makes it important to determine these intensities experimentally in such cases as may be theoretically treated. One of these few is the pure rotation spectrum as, for example, that of hydrogen chloride recently determined in absorption by Czerny (1). This spectrum was used by Tolman and Badger (2) in the calculation of integral absorption coefficients, and so for the determination of the experimental Bij's or the probabilities of transition from one energy state of rotation to the next higher in the presence of radiation which may be absorbed. Since, however, this spectrum was investigated with a spectrometer of not very great resolving power, this process may have led to somewhat inaccurate results. In the present article are described new experimental measurements on the same spectrum, and an improved method whereby they are used to determine absolute absorption coefficients.