Correlation of fluorescence spectra with chemical structure of some naphthalene derivatives

A definite relation is shown to exist between the chemical constitution of certain naphthalene derivatives and their fluorescence and absorption behavior. The naphthalene, naphthylamine and naphthol compounds vary in intensity and region in which they fluorescence. When a radical is changed from an α to a β position, a shift in wave-length of the maximum intensity occurs. From the shape of the densitometer tracings a difference between an acid and its salt is readily discernible.The quality of fluorescence is roughly the same whether the source of excitation be ultraviolet light, X-rays or cathode rays. It is also independent of the concentration and, in the case of the specimens studied, independent of small amounts of impurities.