Abstract: A radiation-sensitive emulsion comprised of high chloride silver halide grains having a central portion accounting for up to 99 percent of total silver and containing a first dopant of Formula (I): [RuL6]n wherein n is −2, −3 or −4, and L6 represents bridging ligands which can be independently selected, provided that at least four of the ligands are anionic ligands, and at least one of the ligands is a cyano ligand or a ligand more electronegative than a cyano ligand; and a second dopant comprising an iridium coordination complex having ligands each of which are more electropositive than a cyano ligand; wherein the first dopant and the second dopants are located together in a common dopant band in an interior shell region of the central portion of the silver halide grains that surrounds at least 70 percent of the silver and, with the more centrally located silver, accounts for 90 percent of the silver halide forming the grains, and wherein the second dopant is present in the silver

Abstract: A radiation-sensitive emulsion comprised of high chloride silver halide grains having a central portion accounting for up to 99 percent of total silver and containing a first dopant of Formula (I): [ML6]n wherein n is zero, −1, −2, −3 or −4; M is a filled frontier orbital polyvalent metal ion, other than iridium, and L6 represents bridging ligands which can be independently selected, provided that at least four of the ligands are anionic ligands, and at least one of the ligands is a cyano ligand or a ligand more electronegative than a cyano ligand; wherein a second dopant comprising an iridium coordination complex having ligands each of which are more electropositive than a cyano ligand is located together with the first dopant in a common dopant band within the central portion of the silver halide grains.

Abstract: A radiation-sensitive emulsion comprised of silver halide grains (a) containing greater than 50 mole percent chloride, based on silver, (b) having greater than 50 percent of their surface area provided by {100} crystal faces, and (c) having a central portion accounting for up to 99 percent of total silver and containing a first dopant of Formula (I) and a second dopant of Formula (II): [RuL6]n  (I) wherein n is zero, −1, −2, −3 or −4, and L6 represents bridging ligands which can be independently selected, provided that at least four of the ligands are anionic ligands, and at least one of the ligands is a cyano ligand or a ligand more electronegative than a cyano ligand; [TE4(NZ)E′]r  (II) wherein T is Os or Ru; E4 represents bridging ligands which can be independently selected; E′ is E or NZ; r is zero, −1, −2 or −3; and Z is oxygen or sulfur; wherein the dopant of Formula (II) is selected from hexacoor

Abstract: A photographic silver halide emulsion is disclosed comprised of radiation sensitive composite silver halide grains including host grain portions accounting for at least 50 percent of total silver and surface portions epitaxially deposited on the host grain portions. The epitaxially deposited surface portions on the host grain portions exhibit a face centered cubic crystal lattice structure containing a hexacoordination complex of a metal from periods 4, 5 and 6 of groups 3 to 14 inclusive of the periodic table of elements in which one or more organic ligands each containing at least one carbon-to-carbon bond, at least one carbon-to-hydrogen bond or at least one carbon-to-nitrogen-to-hydrogen bond sequence occupy up to half the metal coordination sites in the coordination complex and at least half of the metal coordination sites in the coordination complex are provided by halogen or pseudohalogen ligands.

Abstract: A process is disclosed of preparing a radiation sensitive silver halide emulsion comprising reacting silver and halide ions in a dispersing medium in the presence of a metal hexacoordination or tetracoordination complex having at least one organic ligand and at least half of the metal coordination sites occupied by halide or pseudohalide ligands. The metal forming the complex is chosen from periods 4, 5 and 6 and groups 3 to 14 inclusive of the periodic table of elements. The incorporation of the transition metal ion dopant and at least one organic ligand into the cubic crystal lattice of the silver halide grains can be used to improve photographic performance.

Abstract: A process is disclosed of preparing a radiation sensitive silver halide emulsion comprising reacting silver and halide ions in a dispersing medium in the presence of a metal hexacoordination or tetracoordination complex having at least one organic ligand containing a least one carbon-to-carbon bond, at least one carbon-to-hydrogen bond, or at least one carbon-to-nitrogen-to-hydrogen bond sequence and at least half of the metal coordination sites occupied by halide or pseudohalide ligands. The metal forming the complex is chosen from periods 4, 5 and 6 and groups 3 to 13 inclusive of the periodic table of elements. The incorporation of the transition metal ion dopant and at least one organic ligand into the cubic crystal lattice of the silver halide grains can be used to improve photographic performance.

Abstract: Photographic silver halide emulsions are disclosed comprised of radiation sensitive silver halide grains containing greater than 50 mole percent chloride and less than 5 mole percent iodide, based on total silver, with any residual halide being bromide, said grains exhibiting a face centered cubic crystal lattice structure formed in the presence of a hexacoordination complex of rhenium, ruthenium, or osmium with at least four cyanide ligands. The emulsions exhibit increased sensitivity.

Abstract: Photographic emulsions are disclosed comprised of radiation sensitive silver bromide grains optionally containing iodide. The grains exhibit a face centered cubic crystal lattice structure and are formed in the presence of a hexacoordination complex of rhenium, ruthenium, or osmium with at least four cyanide ligands.

Abstract: A photographic silver halide emulsion is disclosed comprised of radiation sensitive silver halide grains exhibiting a face centered cubic crystal lattice structure and internally containing rhenium ions.