Synthesis, Crystal Structure and Luminescence of a New Two-dimensional Pb(Ⅱ) Coordination Polymer

A new two-dimensional Pb(Ⅱ) coordination polymer, [Pb2(L)(tpphz)1.5(NO3)2]·H2O(1), has been obtained by the hydrothermal reaction of tetrapyrido[3,2-a:2′,3′-c:3′′,2′′-h:2′′′,3′′′-j]-phenazine(tpphz) and 2,2′-bipyridyl-3,3′-dicarboxylic acid(H2L). It crystallizes in monoclinic, space group P21/c with a = 15.344(3), b = 14.111(3), c = 21.963(4) ?, β = 106.89(3)o, V = 4550.1(16) ?3, Z = 4, C48H26N13O11Pb2, Mr = 1375.20, Dc = 2.007 g/cm3, F(000) = 2628, μ(Mo Ka) = 7.471 mm-1, R = 0.0339 and w R = 0.0808. In 1, the two crystallographically independent tpphz ligands adopt the same bis-chelating coordination mode, but they play different roles in the structure of 1. One type of tpphz ligands bridge the Pb(Ⅱ) cations to generate a zigzig chain, where the L anions are located on one side of the chain. Further, adjacent chains are linked by the other type of tpphz ligands into a two-dimensional layer structure. Additionally, the solid state luminescent property of 1 was also studied at room temperature.