A novel 3D silver(I) coordination polymer exhibiting unprecedented μ3- and μ4-bonding modes of 2-aminopyrazines

The unprecedented mu(3)- and mu(4)-bonding modes of NH(2)pyz (NH(2)pyz = 2-aminopyrazine) are observed for the first time in a novel 3D Ag(I) coordination polymer [Ag-7(NHpyz)(6)(ClO4)](n) (1) which was obtained by reaction of Ag2O, NH(2)pyz and NaClO4 in H2O/CH3OH/NH3 media under ultrasonic treatment. Compound I is a 3D framework with infinite 1D Ag belts incorporating diverse Ag center dot center dot center dot Ag interactions. Moreover, 1 exhibits photoluminescence maximized at 494 nm upon 300 nm excitation at room temperature, which may be mainly assigned to ligand-to-metal charge transfer (LMCT) mixed with metal-centered (d-s/d-p) transitions. Semiconducting behavior of I was also measured at room temperature with sigma value of 6.78 x 10(-6) S cm(-1). (C) 2009 Elsevier B.V. All rights reserved.