Date Published: July 01, 2012
Publisher: International Union of Crystallography
Author(s): Rui Xu, Jian-Lan Liu.
The title complex, [Mn2(C18H4O10)(H2O)4]n, was synthesized from manganese(II) chloride tetrahydrate and 9,10-dioxo-9,10-dihydroanthracene-1,4,5,8-tetracarboxylic acid (H4AQTC) in water. The anthraquinone unit is located about a crystallographic center of inversion. Each asymmetric unit therefore contains one MnII atom, two water ligands and one half AQTC4− anion. The MnII atom is coordinated in a distorted octahedral geometry by four O atoms from three AQTC4− ligands and two water O atoms. Two of the carboxylate groups coordinate one MnII atom in a chelating mode, whereas the others each coordinate two MnII atoms. Each AQTC4− tetra-anion therefore coordinates six different MnII ions and, as a result, a three-dimensional coordination polymer is formed. O—H⋯O hydrogen bonds, some of them bifurcated, between water ligands and neighboring water or anthraquinone ligands are observed in the crystal structure.
For general background to metal-organic frameworks, see: Li et al. (1999 ▶, 2012 ▶); Cheng et al. (2010 ▶); Hong et al. (2009 ▶); Miller & Gatteschi (2011 ▶); Liu et al. (2010 ▶).