Structure and Optical Property of a New 1D Iodoplumbate Hybrid Directed by in situ Synthesized Asymmetrical N-benzyl-1,4-diazabicyclo[2.2.2]octane

Simple solvothermal reaction of PbI_2,1,4-diazabicyclo[2.2.2]octane and benzyl alcohol in the presence of HI acid creates a new organically templated iodoplumbate hybrid:[(N-Bz-DABCO)(PbI_3)]_n(1,N-Bz-DABCO+ = N-benzyl-1,4-diazabicyclo[2.2.2]octane).Compound 1 crystallizes in orthorhombic space group P2_12_12_1 with a = 20.044(9),b = 8.002(3),c = 12.345(5) ?,V = 1980.1(14) ?~3,Z = 4,C_(13)H_(19)N_2PbI_3,M_r = 791.19,D_c = 2.654 g/cm~3,F(000) = 1408,μ(Mo Kα) = 13.189 mm–1,the final R = 0.0303 and w R = 0.0849 for 3777 observed reflections(I 2σ(I)).Compound 1 contains one-dimensional anionic [PbI_3]nn-chains that are enclosed into the cationic channel formed from the N-benzyl-1,4-diazabicyclo[2.2.2]octane.Noteworthy,compared with common symmetrical N,N?-dialkyl-DABCO~(2+) cations,in-situ formed asymmetrical N-monoalkyl-DABCO~+ cation is first used as structure directing agents/templating agents in the haloplumbate system,finally leading to the occurrence of noncentrosymmetric feature in compound 1.In addition,UV-Vis absorption spectrum analysis reveals that compound 1 is a potential semiconductor material with energy gap of 2.80 eV.     

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