Ag2+ centres are produced in doped and appropriately treated AgCl crystals by irradiation with blue light a t 20 OK. It is shown that the only purpose of the preceding treatment is to create a high concentration of electron traps. I n chalcogen doped crystals (AgCl :S, Se, Te) electron traps are formed by pre-irradiation with blue light above 120 " K ; in iron doped crystds the incorporated Fe2+ ions are converted to Fe3+, acting as traps, either by irradiation a t 20 "C or by annealing in chlorine gas. As the paramagnetic data of the localized Ag2+ centres are independent of the kind of the impurity, one must conclude that the hole is trapped in the undisturbed lattice.Ag2+-Zentren werden in dotierten und geeignet behandelten AgC1-Kristallen durch Bestrahlung mit blauem Licht bei 20 O K erzeugt. Es wird gezeigt, daB die Aufgabe der Vorbehandlung allein darin besteht, eine hohe Konzentration von Elektronenfallen zu schaffen.I n chalkogen-dotierten Kristallen (AgC1: S, Se, Te) wird die Bildung von Elektronenfallen durch Vorbestrahlung mit blauem Licht oberhalb von 120 OK bewirkt ; in eisen-dotierten Kristallen werden die eingebauten Fez+-Ionen entweder durch Bestrahlung bei 20 "C oder durch Tempern in Chlorgas in Fe3+ umgeladen, das als Fanger dient. Da die paramagnetischen Daten der lokalisierten Agz+-Zentren unabhangig von der Art des Zusatzes sind, muB man auf einen Einfang der Defektelektronen im ungestorten Gitter schlieSen.
SgC1-and AgBr-crystals, containing divalent nickel, incorporated partly isolated partly in association with silver vacancies, are irradiated with light a t low temperatures. Hereby the isolated nickel ions are converted to in the monovalent state.AgCl-und AgBr-Kristalle mit zweiwertigem Nickel, das teils isoliert, teils assoziiert mit Silberionenlucken eingebaut ist, wurden bei tiefer Temperatur mit Licht bestrahlt. Dabei werden die isolierten Nickelionen in den einwertigen Zustand umgeladen.
ESR measurements are made on Xi-doped AgCl at low temperatures. As in the case of AgBr :Ki, already investigated, a line with isotropic g-value is found, due to isolated Ni2+. Moreover an angular dependent spectrum with nearly [100]-axial symmetry is observed, which is attributed to complexes of Ni2+ with a silver vacancy. Contrary to the results on AgBr:Ni a structure of the anisotropic spectrum is observed in a small angular range, which may be explained only by the presence of very small orthorhombic perturbations.It is shown, that these orthorhombic perturbations of different quantities result from the variant distributions of both the isotopes 35Cl and 37C1 in the plane perpendicular to the axis of the centre.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.