ATOMIC-FORCE MICROSCOPY STUDIES OF AGBR CRYSTALS

Atomic force microscopy (AFM) has become a very powerful tool for investigations of nearly any kind of surface. For the silver halides AFM opens a new, very promising way to enhance knowledge about the surface structures of AgX emulsion grains down to the atomic scale, helping to gain a deeper understanding of all surface-related factors and mechanisms determining sensitization behavior and latent image growth. In this study, AFM investigations of AgBr model systems, as well as emulsion grains, are especially focused on the AgBr (111) crystal plane. Data indicate that the (111) surfaces of evaporation layers, as well as of octahedral and cubooctahedral emulsion grains, are realized by an arrangement of ions on a full (111) plane showing distorted hexagonal symmetry. Superstructures that have been revealed are assumed to be induced by the distortion.