Mn(II) staircase structures stitched by water clusters to a 3D metal-organic open framework: X-ray structural and magnetic studies

4-Hydroxypyridine-2,6-dicarboxylic acid (chelidamic acid, cdaH(2)) reacts with Mn(OAC)(2)-4H2O to form a 1 D staircase structure with dimeric Mn(II) units connected by water clusters to form a 3D framework, { [Mn-2(cda)(2)center dot 4H(2)O]center dot 4H(2)O in, 1, in aqueous pyridine at room temperature. The compound crystallizes in the triclinic space group F with a = 9.495(3), b =10.733(5), c = 11.065(4) angstrom, beta = 87.42(5), = 74.14(5), gamma = 80,07(2)degrees, U = 1068.5(g) angstrom(3), Z = 2, rho(calcd) = 1.915 g cm(-3), T = 100 K, mu = 1.28 mm(-1), R, 0.0453 (1 > 2 sigma(1)), wR(2) = 0.1046, GOOF = 1.282, Upon removal of the water molecules by heating, the 3D structure breaks down. Thermogravimetric analysis, infrared, X-ray powder diffraction studies, and X-ray crystallography were performed to characterize this compound. Since the coordination polymer has diaqua-bridged Mn(ll) centers, it was subjected to variable-temperature magnetic studies.