A novel heterometallic complex, [Ni2Mn(N-3)(2)(nic)(4) center dot (H2O)(2)](n) (1) (nic=nicotinate), was obtained by assembling MnCl2 center dot 4H(2)O, Ni(NO3)(2)-6H(2)O, NaN3 and nicotinic acid with a "one step" synthetic strategy-hydrothermal reaction. The 3D structure of the complex can be described as end-on (EO) azido and syn, syn carboxylates mixed bridged by alternate Ni-Mn-Ni trimers linked by the nicotinate. Dominant ferromagnetic interactions were observed between the Ni-II and Mn-II ions in the trimer. (C) 2013 Elsevier Inc. All rights reserved.

Two new lanthanide-azide complexes, [Ln2(N3)(isonic)2(OH)3(Hisonic)(H2O)]n (Ln=Yb for 1 and Tb for 2, isonic=isonicotinate), were obtained in hydrothermal condition. X-ray diffraction analysis indicated the two complexes are isomorphic chain structure in which the LnIII ions are mixed bridged by the azide anions, hydroxyl anions and carboxylate groups of the isonicotinate ligands. Further studies indicated weak antiferromagnetic interactions between the LnIII ions in 1 and 2, and complex 2 exhibit green sensitized Luminescent character of TbIII ion.

Two new manganese complexes, [Mn3(L1)4(NO3)2]n (1, HL1=nicotinate N-oxide acid) and [MnL2Cl]n (2, HL2=isonicotinate N-oxide acid)], have been hydrothermally synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. In 1, the L1 ligands take two different coordinated modes bridging four and three MnII ions. The nitrate anions take chelating coordination modes, leading one type of the MnII ions as a 4-connected node. The whole net can be viewed as a 3, 4, 6-connected 4-nodal net with Schläfli notation {43}2{44; 62}4{46; 66; 83}. Complex 2 has a honeycomb layer mixed bridged by chlorine, N-oxide and carboxylate. The adjacent layers are linked by the phenyl ring of L2 ligand, giving a 3D framework with a {34; 54} {32;4;56;66} 4, 6-connect net. Magnetic studies indicate that 1 is an antiferromagnet with low-dimensional characteristic, in which a –J1J1J2– coupled alternating chain is predigested. Fitting the data of 1 gives the best parameters J1=−2.77, J2=−0.67cm−1. The magnetic properties of complex 2 represent the character of the 2D honeycomb layer with the J1=−2.05 and J2=0.55cm−1, which results in a whole antiferromagnetic state.

Two new Co(II) complexes, [Co(OCH(3))L] (1) and [Co(3)(N(3))(4)(OCH(3))(2)L(2)] (2) (L = isonicotinate N-oxide), were synthesized by solvothermal reaction and magnetically characterized. The cobalt ions in 1 and 2 all exhibit distorted octahedral coordination geometry. In 1, there is a mu(11)-methoxy/syn,syn-carboxylate mixed coordinated cobalt chain with mixed coordination, and a 3D structure is formed by the chains linked through the L ligands. In 2, the alternating Co(II) chains that are formed by linking the double end-on azide-bridged trimers are connected by the L ligands to form a 2D layer. Magnetic studies revealed that ferromagnetic coupling exists between the Co(II) ions in 1, and 1 undergoes a ferromagnetic transition at 2.5 K, whereas alternating ferromagnetic (FM) and antiferromagnetic (AFM) interactions exist in the chain of 2.

In the title compound, [Co(C(6)H(3)N(4)O(2))(2)(H(2)O)(2)]·2H(2)O, the Co(II) atom is located on an inversion center in a slightly distorted octa-hedral environment formed by the O atoms of two water mol-ecules, and the N and O atoms of the chelating tetra-zolo[1,5-a]pyridine-8-carboxyl-ate anions. Hydrogen bonds of the O-H⋯O and O-H⋯N types result in a three-dimensional supra-molecular network.

In the title compound, [Co(C6H3N4O2)2(H2O)2]·2H2O, the CoII atom is located on an inversion center in a slightly distorted octahedral environment formed by the O atoms of two water molecules, and the N and O atoms of the chelating tetrazolo[1,5-a]pyridine-8-carboxylate anions. Hydrogen bonds of the O—H...O and O—H...N types result in a three-dimensional supramolecular network.