Hydrothermal syntheses, crystal structures and characterizations of three new copper coordination polymers

Three new copper complexes, [(CuCuI)-Cu-II(ip)(ipH)(4,4'-bipy)(3/2)](n) (1), [Cu(ip)(4,4'-bipy)](n)center dot 3nH(2)O (2), and [Cu(ipH)(2)(4,4'-bipy)](n), (3), have been hydrothermally synthesized by the reaction of Cu(NO3)(2) center dot 3H(2)O with isophthalic acid (ipH(2)) and 4,4'-bipyridine (4,4'-bipy) under different reaction conditions. Complex 1, a mixed-valence copper(1,11) complex, exhibits a 2-D) interpenetrating grid framework, in which five-coordinated Cull and three-coordinated Cu-I environments are established. The oxidation states of center Cu atoms have been confirmed by X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance spectra (EPR). Complex 2 features a 2-D box-like bilayer architecture, in which Cull atoms are linked by ip ligands to form a 1-D double-chain and the resulting chains are further strutted by the 4,4'-bipy ligands. In complex 3, two bridging 4,4'-bipy ligands and two terminal ipH ligands confine the Cull center in a square plane coordination geometry. The whole molecule of 3 was arranged into a 1-D linear chain structure. Additionally, the thermogravimetric analyses (TGA) for complexes 1-3 are also discussed in this paper. (c) 2005 Elsevier B.V. All rights reserved.