title: Magnetic resonance study of Rh complexes in AgCl microcrystals.
abstract: X-ray or UV irradiation at room temperature of Rh3+ doped AgCl emulsion powders leads to the production of three paramagnetic Rh2+ related centres, labeled R4, R5 and R6. A combined X and Q band electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) study allowed the determination of a nearly complete structural model for these centres. In the X band ENDOR spectra of R4 and R5 interactions of the unpaired electron with nearby protons have been identified, indicating that for these centres Cl- ligands have been exchanged by H2O or OH-. The R6 centre, identified as a (RhCl6)4- complex, has been found to be fundamentally different from the dominant centre in large Rh2+ doped AgCl single crystals grown from the melt. The results are compared with recent work by other researchers in the same field.
authors.affiliation: Laboratory for Crystallography and Study of the Solid State, Gent, Belgium.
authors.forename: H
authors.initials: H
authors.lastname: Vrielinck
authors.forename: K
authors.initials: K
authors.lastname: Sabbe
authors.forename: F
authors.initials: F
authors.lastname: Callens
authors.forename: P
authors.initials: P
authors.lastname: Matthys
authors.forename: D
authors.initials: D
authors.lastname: Vandenbroucke
mesh_terms: D003460:Crystallization; D004578:Electron Spin Resonance Spectroscopy; D008956:Models, Chemical; D012238:Rhodium / Q000737:chemistry* / Q000528:radiation effects; D018030:Silver Compounds / Q000737:chemistry* / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D018030:Silver Compounds; D012238:Rhodium; C037548:silver chloride