Synthesis, Crystal Structure and Fluorescent Property of [Ag3（μ3-I）2（μ2-dppm）3]I·0.5THF·0.5 H2O

The crystal structure of the title complex, [Ag3(μ3-I)2(μ2-dppm)3]I·0.5THF·0.5H2O (dppm = bis(diphenylphino) methane and THF = tetrahydrofuran), has been determined by single- crystal X-ray diffraction, revealing it consists of a trinuclear [Ag3I2(dppm)3]+ cation with a tri- gonal bipyramidal [Ag3(μ3-I)2] cluster, a discrete iodine anion, one half THF and one half H2O solvent molecules. The short Ag…Ag distances (Ag(1)…Ag(2) = 3.1307(4), Ag(1)…Ag(3) = 3.2527(4) and Ag(2)…Ag(3) = 3.3209(4) (A)) in the cluster suggest the existence of argentophilic interactions between the silver atoms. The crystal belongs to monoclinic, space group P21/n with a = 19.172(2), b = 18.819(1), c = 21.316(1) (A), β = 91.081(4)°, V = 7689.4(9) (A)3, Dc = 1.643 g/cm3, Z = 4, C77H71Ag3I3OP6, Mr = 1902.47, μ = 2.127 mm-1, λ(MoKα) = 0.71073 (A) And F(000) = 3724. The final R = 0.0584 and Wr = 0.0928 for 8470 observed reflections with I > 2σ(I). The electronic emission spectrum shows a broad band around 408 nm which is assigned to the ligand-to-metal charge-transfer (LMCT) [I- → Ag3] excited state, mixed with a metal-centred (ds/dp) state.