An Analysis of Sulfur Sensitization Centers and Fog Centers by Applying Diffuse Reflectance Spectroscopy to Thick Emulsion Layers

Abstract

By applying diffuse reflectance spectroscopy to 0.2μm octahedral AgBr emulsions which were digested in the presence of various amount of sulfur sensitizers, the absorption bands of sulfur sensitization centers and fog centers were distingished from each other. The absorption band of fog centers was recognized for the first time as a wide one extending from 500 nm to 780 nm. Sulfur sensitization centers were identified as the species that had the absorption band at 520 nm, as Moisar had already done. The activation energies for the formation of sulfur sensitization centers and sulfur fog centers as measured on the basis of the above- stated observation were estimated 32.0 kcal/ mol and 39.8 kcal/ mol, respectively.