Chemical modification utilizing a terminal structure exposed on the specific surface of polymer-metal complex nanocrystals

It has been difficult to selectively modify the surface of molecular crystals by chemical reactions because they usually have no reaction points on their surfaces. In this paper, focusing on the unique nanocrystal surface of the polymer metal complex (PMC) [{Cu 2 (μ-Br) 2 (PPh 3 ) 2 }(μ-bpy)] n having an exposed reactive terminal chain, we successfully modified the surface of PMC nanocrystals (NCs) through an alkylation reaction. Interestingly, after the alkylation reaction, the luminescence spectrum of PMC NCs blue-shifted, and the luminescence quantum yield increased. PMC NCs with a large specific surface area showed optically peculiar or characteristic properties compared with the corresponding bulk crystals. PMC NCs have high potential as a new class of luminescent materials due to their surface effect. We modified the surface of polymer metal complex nanocrystals (PMC NCs) with the alkylation reaction by utilizing coordinatively unsaturated bipyridine ligands exposed on the (010), and successfully changed the luminescence properties of PMC NCs.