Abstract: A series of octahedral emulsion microcrystal with different iodide content was prepared by double-jet method with automatic control of pAg. Their light absorption, ionic and pho-toelectron conductivities were determined as a function of iodide content. It was shown hat the light absorption and ionic conductivity increase obviously with the iodide content increase. The same dependence is also with the photo-conductivity. The photoelectron decay obeys a second order reaction kinetic, the photoelectron lifetime increase with the iodide increase (0-5mol% range), reaching a maximum at 5mol% iodide content, and then turning to decrease a bit (7.5-12.5mol% range). Under the same sensitization conditions the photographic sensitivity of the emulsion microcrystals heightens with the increase of iodide content introduced during the preci pitation.

Key words: photographic chemistry, core-shell emulsion, ionic conductivity, photoconductivity, light absorption