The puzzling structural details of the mixed oxide AgCuO2 are shown to be related to a charge transfer between the AgO2 extended units and the CuO2 chains. As a result the system behaves as a metal and the silver atoms form quite stable chains that can easily slide among the CuO2 chains.
Charge Delocalization, Oxidation States, and Silver Mobility in the Mixed Silver−Copper Oxide AgCuO2
Abel Carreras, Sergio Conejeros, Agustín Camón, Alberto García, Nieves Casañ-Pastor, Pere Alemany, Enric Canadell
Inorganic Chemistry 58, 7026−7035, 2019
Figure: The crystal structure of AgCuO2 is built from the condensation of CuO2 chains and AgO2 units (top left). As a result of an electron transfer between formally Ag+ and Cu3+ d levels a Fermi surface (top right) with Ag and Cu contribution is created leading to a metallic behavior. Such transfer stabilizes oxidized silver and oxidized copper, and the structure may be described as Ag-O planes with intercalated Cu-O chains in between (center down).