Design and Construction of Coordination Polymers by 4-Amino-3,5-bis(n-pyridyl)-1,2,4-triazole (n=2, 3, 4) Isomers in a Copper(I) Halide System: Diverse Structures Tuned by Isomeric and Anion Effects

Twelve Cu(I) coordination polymers, [CuCl(L1)](n) (1), [Cu4I4(L1)(2)](n) (2), {[Cu2I2(L1)]center dot 0.5I(2)}(n) (3), [Cu3I3(Ll)](n) (4), [Cu2Br2(L1)](n) (5), [CuBr(L1)](n) (6), [Cu2Cl2(L1)](n) (7), [Cu2Br2(L2)](n) (8), [CuBr(L2)](n) (9), [CuI(L-2)](n) (10), [Cu3I3(L2)](n) (11), and Cu2I2(L3)(2) (12) (L1 = 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole, L2 = 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole and L3 = 4-amino-3,5-bis(2-pyridyl)-1,2,4-triazole), have been prepared and structurally characterized. In these compounds, 4-amino-3,5-bis(n-pyridyl)-1,2,4-triazole (n-bpt) exhibits different coordination modes tuned by the isomeric effect and the anion effect, forming various architectures by bridging a variety of CuX (X = Cl, Br, or I) building units. Compound 1 presents a layer structure with (4, 4) topology built by bridging adjacent (CuCl)(infinity) chains with L1. Compound 2 shows an unusual onedimensional strap structure by linking a rare Cu(8)l(8) unit with L1. Compounds 3 and 4 present two-dimensional layers with (6, 3) topology. Compound 5 shows a three-dimensional ZnCl2 network with {3.6.7(4)}{3.6(2).7(3)}(2) topology. Compound 6 exhibits a layer with (4, 8(2)) network topology. A complicated three-dimensional framework for 7 is constructed with unique {6.8(2)}(2){6.8(5)} topology. Compounds 8 and 9 are both chains, and hydrogen-bonding and pi-pi interactions play important roles in stabilizing the extended structure. Compound 10 is a layer with (4, 4) topology. An interesting double layer compound exhibiting complicated structure is found for 11. Compound 12 is a zero-periodic compound. The luminescent properties of compounds 4-6, 8, 9, and 12 have been investigated in the solid state.