Particulate processes in freshly prepared silver iodide hydrosols part III. Disagreement between experimental results and the existing models of silver iodide hydrosols

Abstract

Silver iodide hydrosols prepared in statu nascendi exhibit some specific effects that cannot be explained on the basis of the existing models of silver iodide hydrosols. These effects are acceleration of a heterogeneous exchange process caused by coagulation of the system, and different aggregation number obtained in the same system applying two different exchange methods. In order to explain these effects, a comparison has been made of the differences between the data calculated on the basis of the existing model of silver iodide hydrosols and the values determined by radiometric, optic, and sedimentation analysis. The previous assumption on the existence of a new structural form of silver iodide, characteristic of stable silver iodide hydrosols, has been confirmed. This new structural form of silver iodide transforms into known hexagonal and cubic modifications during the aggregation of primary particles of silver iodide to secondary ones. The properties of the new structural form of silver iodide are predicted.