Directional Energy Transfer in Mixed-Metallic Copper(I)–Silver(I) Coordination Polymers with Strong Luminescence

Strongly luminescent mixed-metallic
copper­(I)–silver­(I) coordination polymers with various Cu/Ag
ratio were prepared by utilizing the isomorphous relationship of the
luminescent parent homometallic coordination polymers (Φem = 0.65 and 0.72 for the solid Cu and Ag polymers, respectively,
at room temperature). The mixed-metallic polymer with the mole fraction
of copper even as low as 0.005 exhibits a strong emission (Φem = 0.75) from only the copper sites as the result of the
efficient energy migration from the silver to the copper sites. The
migration rates between the two sites were evaluated from the dependence
of emission decays upon the mole fraction of copper.