X-ray structures and emissive and second-order nonlinear optical properties of two inorganic-organic polymeric adducts of CuI with 4-acetylpyridine.: The role of both "intrastrand" charge transfers and structural motifs on the nonlinear optical response of Cu(I) polymeric adducts with pseudoaromatic η1-nitrogen donor ligands

X-ray crystal structures, solid-state photoluminescence, and Kurtz-Perry powder second harmonic generation (SHG) efficiencies of two novel noncentrosymmetric polymeric adducts of CuI with 4-acetylpyridine, a double-stranded "stair" and a single-stranded "chain", are reported, the latter being a rare example of a [CuX(L)(2)](n) motif (X = halide, L = pseudoaromatic eta(1)-nitrogen donor ligand). In a series of structurally related noncentrosymmetric [CuX(L)](n) chains and stairs, the powder SHG responses are interpreted in terms of both structural motifs (chains showing definitely greater efficiency than stairs) and "intrastrand" charge transfers involving the bridging halides.