Aghabozorg Hossein, Derikvand Zohreh, Olmstead Marilyn M, Attar Gharamaleki Jafar
Faculty of Chemistry, Tarbiat Moallem University, Tehran, Iran.
Acta Crystallogr C. 2008 Nov;64(Pt 11):m372-4. doi: 10.1107/S0108270108032204. Epub 2008 Oct 18.
For charge balance in the title compound, (H(5)O(2))(C(3)H(7)N(6))(3)Mn(C(7)H(3)NO(4))(2)(OH).C(7)H(5)NO(4).5H(2)O, it is assumed that the metal atom site is disordered Mn(II)/Mn(III), probably due to partial air oxidation of the starting Mn(II) species. The formula unit of the complex contains a hydroxonium hydrate cation, H(5)O(2)(+), also known as the Zundel cation, with twofold symmetry. The O...O [2.445 (10) A] and O...H distances [1.24 (2) A] in the H(5)O(2)(+) cation indicate a strong hydrogen bond. In addition, there is a hydroxide ion that is disordered with respect to a twofold rotation axis. One of the melaminium groups and the pyridine-2,6-dicarboxylate (pydc) ligand also reside on crystallographic twofold axes. The coordination environment of the Mn ion is distorted octahedral. Three intermolecular C=O...pi interactions are observed, with distances of 3.536 (4), 3.262 (4) and 3.750 (4) A between carboxylate C=O groups and the centroids of the aromatic rings of pydc and melaminium. There are numerous O-H...O, O-H...N, N-H...O, N-H...N and C-H...O hydrogen bonds. Most of the components of the structure are organized into one plane.
对于标题化合物(H(5)O(2))(C(3)H(7)N(6))(3)Mn(C(7)H(3)NO(4))(2)(OH).C(7)H(5)NO(4).5H(2)O中的电荷平衡，假设金属原子位点为无序的Mn(II)/Mn(III)，这可能是由于起始Mn(II)物种的部分空气氧化所致。该配合物的化学式单元包含一个水合氢离子阳离子H(5)O(2)(+)，也称为祖德尔阳离子，具有二重对称性。H(5)O(2)(+)阳离子中的O...O [2.445 (10) Å]和O...H距离[1.24 (2) Å]表明存在强氢键。此外，有一个氢氧根离子相对于二重旋转轴无序。其中一个三聚氰胺基团和吡啶-2,6-二羧酸酯(pydc)配体也位于晶体学二重轴上。Mn离子的配位环境为扭曲八面体。观察到三个分子间C=O...π相互作用，羧酸根C=O基团与pydc和三聚氰胺的芳环质心之间的距离分别为3.536 (4)、3.262 (4)和3.750 (4) Å。存在大量的O-H...O、O-H...N、N-H...O、N-H...N和C-H...O氢键。结构的大多数组分排列在一个平面内。
