Some Features in the Absorption Spectra of Silver Halides and Thin Metallic Layers

Original Russian M.S. received 14 February 1968. English Translation made by S.C. Goddard, Research Laboratories, Kodak Limited, received 15 March 1968.

Abstract

Kirillov and his school in the Soviet Union, using a differential method, observed a fine-structure in the absorption spectra of photographic emulsions, silver-halide crystals, and thin layers of metallic silver. This fine-structure was ascribed to impurity centres, and the method was taken up by a number of other Soviet authors to study the nature and reactions of the sensitivity centres and latent-image centres of photographic materials. Some authors, however, have questioned the findings and suggested that the fine-structure could be an interference effect. The Russian work is reviewed in some detail, and it is shown that the possibility of the results being due to interference has been eliminated, and that the fine-structure is best explained as due to the absorption of light by impurity centres consisting of a few atoms of metallic silver in an aggregate of sub-colloidal dimensions.

Notes

Original Russian M.S. received 14 February 1968. English Translation made by S.C. Goddard, Research Laboratories, Kodak Limited, received 15 March 1968.