Syntheses, Structures, Photochemical and Magnetic Properties of Novel Divalent Cd/Mn Coordination Polymers Based on a Semirigid Tripodal Carboxylate Ligand

The reactions of a semirigid tripodal carboxylic ligand, 3,5-bi(4-carboxy-phenoxy)-benzoic acid (H(3)BCPBA) with Cd(NO3)(2)/Mn(NO3)(2) afford five novel complexes, {[Cd-3(BCPEA)(2)center dot(DMA)(2)center dot(H2O)(5))center dot 7H(2)O.2DMA}(n) (1), {[Cd-3(BCPBA)(2)(L-1)(H2O)(6)]center dot(L-1)}(n) (L-1 = 4-[(E)-4-pyridinylazo]pyridine) (2), {[Cd-3(BCPBA)(2)(L-2)center dot(H2O)(3)(DMF)(2)]center dot 2DMF}(n) (L-2 = 1,3-bis(4-pyridyl)propane) (3), {[Mn-3(BCPBA)(2)(H2O)center dot 11H(2)O}(n) (4), {[Mn-3(BCPBA)(2)(DMF)(2)(H2O)(2)]center dot 2DMF.9H(2)O} (5) in the presence or absence of an auxiliary ligand. Compound 1 is a three-dimensional (3D) structure with 3,4-connected net structure. Compound 2 possesses 3D networks with two 3D 0 3D interpenetration frameworks. Compound 3 is a 3D sheet structure with a decorated tfz-d topology. Compound 4 is a 3D structure which consists of a two-dimensional (2D) Mn honeycomb net with six infinite Mn rings and BCPBA(3-) ligands. Compound 5 is also a 3D structure, while its 2D Mn honeycomb net with eight infinite Mn rings is different from that of compound 4. The photochemical property of 1-3 is performed in the solid state at room temperature Magnetic susceptibility measurements indicate that compounds 4 and 5 exhibit antiferromagnetic coupling between adjacent Mn(II) ions.