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C38H34Ni2Cl2N4O12, monoclinic, C2/c (no. 15), a = 17.867(3) Å, b = 9.170(6) Å, c = 24.651(5) Å, β = 110.837(2)°, Z = 4, V = 3775(3) Å3, Rgt(F) = 0.0323, wRref(F2) = 0.1078, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Two binuclear lanthanide complexes [Ln 2 (hfac) 6 (HL) 2 ] (Ln III = Dy( 1 ), Tb( 2 ); hfac = hexafluoroacetylacetonate, HL = (R)-2-amino-2-phenylethanol) have been successfully obtained by using amino alcoholate ligand. In two complexes, the Ln(III) ions are bridged by two alkoxido groups from HL ligands, resulting in binuclear complexes. The variable-temperature magnetic susceptibility studies indicate that there exists ferromagnetic interaction between two Ln(III) ions. Frequency dependent out-of-phase signals are observed for complex 1 , suggesting SMM type behavior. Complexes 1 and 2 display intensely characteristic luminescent properties. [ABSTRACT FROM AUTHOR]

Based on the bis-triazole ligand 2, 6-bis(1, 2,4-triazole-4-yl)pyridine (L), the triazole-iron(II) complexes [Fe(L)2(dca)2(H2O)2] ·2H2O ( 1) (Nadca = sodium dicyanamide), {[Fe(μ2-L)2(H2O)2]Cl2} n ( 2), and {[Fe(μ2-L)2(H2O)2](ClO4)2 ·L ·H2O} n ( 3) were isolated by solvent diffusion methods. When iron(II) salts and Nadca were used, compound 1 was isolated, which contains mononuclear Fe(L)2(dca)2(H2O)2 units. When FeCl2 or FeClO4 were used, one-dimensional (1D) cation iron(II) chains ( 2) and two-dimensional (2D) cation iron(II) networks ( 3) were isolated indicating anion directing structural diversity. Moreover, variable-temperature magnetic susceptibility data of 1- 3 were recorded in the temperature range 2-300 K. The magnetic curve of complex 2 was fitted by using the classical spin Heisenberg chain model indicating anti-ferromagnetic interactions ( J = -5.31 cm-1). Obviously complexes 1- 3 show no detectable thermal spin crossover behaviors, the lack of spin-crossover behavior may be correlated with FeN4O2 coordination spheres in 1- 3. [ABSTRACT FROM AUTHOR]

• The Schiff base binuclear Zn(II) complex, [Zn 2 (L) 2 ∙(H 2 O) 2 ]∙2DMF (1) and its coordination polymer, [Zn 2 (L) 2 ∙(4,4′-bpy) 2 ] n (2) by introducing auxiliary ligand 4,4′-bpy. • The fluorescence spectrum showed the complex 2 containing 4,4′-bpy was substantially quenching of the fluorescence as compared with the complex 1. • The LUMO and HOMO orbits of the complex 2 were occupied by the 4,4′-bpy, which is different from complex 1 , resulting in 1 and 2 had different spectral properties. The Schiff base binuclear Zn(II) complexes, [Zn 2 (L) 2 ∙(H 2 O) 2 ]∙2DMF (1) and its coordination polymer [Zn 2 (L) 2 ∙(4,4′-bpy) 2 ] n (2) (H 2 L = 3-[(5-chloro-2-hydroxy-benzylidene)-amino]-4-hydroxy-chromen-2-one, 4,4′-bpy = 4,4′-bipyridine), were synthesized under the same experimental condition without or with the auxiliary ligand 4,4′-bpy, respectively. The structural analysis revealed that complexes 1 and 2 have different crystal structures. The complex 1 was a centrosymmetric binuclear structure. It is noteworthy that the linker 4,4′-bpy was introduced during the synthesis of complex 2 , so that two water molecules in complex 1 were replaced by two 4,4′-bpy linkers to form one-dimensional (1D) chain-like coordination polymer. The central Zn(II) ions in complex 1 were penta-coordinated distorted square pyramid geometry with τ = 0.42. However, the Zn(II) ions of complex 2 were hexa-coordinated distorted octahedral geometry. The fluorescence spectrum showed the complex 2 containing 4,4′-bpy was substantially quenching of the fluorescence as compared with the complex 1. In addition, it could be seen from the DFT calculation the energy gaps of the complexes 1 and 2 were both reduced compared to the ligand H 2 L. However, the LUMO and HOMO orbits of the complex 2 were occupied by the 4,4′-bpy, which is different from complex 1 , resulting in 1 and 2 had different spectral properties. [ABSTRACT FROM AUTHOR]