Open AccessThe origin of the “cyanogen” bands
Author(s) -
S. Barratt
Publication year - 1920
Publication title -
proceedings of the royal society of london. series a, containing papers of a mathematical and physical character
Language(s) - English
Resource type - Journals
eISSN - 2053-9150
pISSN - 0950-1207
DOI - 10.1098/rspa.1920.0050
Subject(s) - cyanogen , nitrogen , chemistry , oxygen , spectral line , ammonia , molecule , impurity , inorganic chemistry , analytical chemistry (journal) , organic chemistry , physics , astronomy
There are, in addition to the line and the positive and negative band spectra of nitrogen, several other series of bands, in the production of which this element plays some part. The emission centres responsible for these bands have generally been identified with the molecules of compounds of nitrogen with other elements, though these molecules are not necessarily those of compounds which can be isolated under normal circumstances, and possibly may prove to be more of the nature of temporary associations. Such spectra include the so-called third positive band spectrum of nitrogen, the various spectra attributed to ammonia or other nitrogen-oxygen complexes, and also the cyanogen bands. The NO bands, Deslandres’ third positive group of nitrogen bands, are found in vacuum tubes filled with nitrogen, when they contain a trace of oxygen as impurity. They have also been observed in the carbon arc surrounded by a magnesia block, in uncondensed spark discharges in air and nitrogen, and in the flames of cyanogen and ammonia. They were formerly believed to be due to nitrogen alone, but Deslandres, Schniederjost, Lewis and others have proved that their production is dependent upon the presence of oxygen.