Absorption Spectrum of Cs in the Presence of Isomeric Hydrocarbons

Abstract
The satellite bands and the shifts of the Cs lines in the spectra of Cs—hydrocarbon mixtures were studied. The hydrocarbons were isomers of butene (butene‐1, butene‐2, isobutene), butane (n‐butane, isobutane), pentane (n‐pentane, isopentane, neopentane), and hexane (n‐hexane, 3‐methylpentane, 2,3‐dimethylbutane, neohexane). Four different types of satellite bands were observed. The shifts of high members of the Cs principal series extrapolated to relative density 1 were 41, 47, 47, 48, 55, 58, and 61 cm—1 for n‐pentane, isopentane, n‐hexane, 3‐methylpentane, 2,3‐dimethylbutane, neopentane, and neohexane, respectively. The results of simultaneous measurements of the band positions and shifts of high members of the Cs principal series suggest that the positions of the high‐intensity red satellite bands are determined primarily by the effective cross sections of foreign‐gas molecules for slow electrons rather than by the mass or polarizability of these molecules as thought previously.