resumo
In this work are presented the synthesis, structure and magnetic measurements for the [Co(mu(2)-biim)(6) 2Co(mu-H2O)(OH)(6)] (biim = 2,2'-biimidazole) metal-organic framework. The compound crystallizes in the cubic system, space group Pa (3) over bar (a = 16.0312(6) angstrom, V = 4120.0(3) angstrom(3) and Z = 4), containing two crystallo-graphically distinct divalent cobalt ions Co(1) and Co(2) six- and seven-coordinated, respectively. The two metal centers are linked by 2,2'-biimidazole bridging ligand through the N(6) nitrogen donor and Co(2) forming a dimer via bridged water molecule with Co-Co distance of 4.313(3) angstrom, originating a 3D structure. Topological analysis of this compound revealed that the structure is an abi-nodal 3,4-connected network with total point symbol {8(3)}{8(6)}. By fitting of susceptibility data to the Curie-Weiss law it was possible to estimate the magnetic parameters theta(p) and p(eff). Magnetic susceptibility results suggest an antiferromagnetic order in the system. (C) 2014 Elsevier Ltd. All rights reserved.
palavras-chave
CRYSTAL-STRUCTURES; COMPLEXES; LIGAND; COORDINATION; CHLORIDE; POLYMER; NETS
categoria
Chemistry; Crystallography
autores
Pedro, SS; Brandao, P; Shi, FN; Tedesco, JCG; Reis, MS
nossos autores
Fa-Nian Shi
Investigador
Paula Cristina Ferreira da Silva Brandão
Investigador AuxiliarProjectos
agradecimentos
S.S. Pedro, J.C.G. Tedesco and M. Reis acknowledge CAPES, CNPq and Proppi-UFF for financial support. P. Brandao acknowledge FCT, European Union, QREN, Fundo Europeu de Desenvolvimento Regional (FEDER) from European commission, COMPETE and CIC-ECO (PEst-C/CTM/LA0011/2011) for their general funding. Shi thanks FCT project (PTDC/CTM-NAN/119994/2010). The authors also thank to Dr. J.P. de Araujo, from Porto University for magnetic measurements and C. Cruz in the interpretation of the magnetic data.