Han Lu, Luo Huan-Mian, Meng Qiu-Hui, Luo Yi-Fan, Zeng Rong-Hua
Acta Crystallogr Sect E Struct Rep Online. 2009 Dec 9;66(Pt 1):o68-9. doi: 10.1107/S1600536809050831.
In the title compound, C(10)H(9)N(2) (+)·C(16)H(9)O(8) (-)·2H(2)O, both the cation and anion possess crystallographically imposed centres of symmetry, causing the nitro-gen-bound H atom in the 4-(4-pyrid-yl)pyridinium cation and the acidic H atom of the carboxyl-ate groups at the 3 and 3' positions in the anion to be disordered over two positions with equal occupancies. In the crystal packing, the cations, anions and water mol-ecules are connected by O-H⋯O, C-H⋯O and N-H⋯N hydrogen bonds, forming layers parallel to (20). These layer are further connected into a three-dimensional supra-molecular network by O-H⋯O hydrogen bonds involving the water mol-ecules as H-atom donors and by weak π-π stacking inter-actions between neighbouring benzene and pyridine rings, with centroid-centroid distances of 3.756 (5) Å.
在标题化合物C₁₀H₉N₂⁺·C₁₆H₉O₈⁻·2H₂O中，阳离子和阴离子均具有晶体学上的对称中心，导致4-(4-吡啶基)吡啶鎓阳离子中与氮相连的氢原子以及阴离子中3和3'位置羧酸盐基团的酸性氢原子在两个位置上无序分布，占有率相等。在晶体堆积中，阳离子、阴离子和水分子通过O—H⋯O、C—H⋯O和N—H⋯N氢键相连，形成平行于(20)的层。这些层通过涉及水分子作为氢原子供体的O—H⋯O氢键以及相邻苯环和吡啶环之间的弱π-π堆积相互作用进一步连接成三维超分子网络，质心间距为3.756 (5) Å。
