Fun Hoong-Kun, Balasubramani Kasthuri
X-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 Universiti Sains Malaysia, Penang, Malaysia.
Acta Crystallogr Sect E Struct Rep Online. 2009 Jul 18;65(Pt 8):o1887-8. doi: 10.1107/S1600536809027354.
In the title compound, C(5)H(8)N(3) (+)·C(7)H(4)NO(4) (-)·C(7)H(5)NO(4), the non-H atoms of the 3,4-diamino-pyridinium cation are coplanar, with a maximum deviation of 0.022 (1) Å. The carboxyl-ate and nitro groups of the 4-nitro-benzoate anion are twisted out of the attached ring planes by dihedral angles of 15.89 (8) and 10.20 (8)°, respectively. In the 4-nitro-benzoic acid mol-ecule, the carboxyl and nitro groups form dihedral angles of 18.25 (8) and 6.55 (8)°, respectively, with the benzene ring. In the crystal, the constituent units form two-dimensional networks parallel to (001) by O-H⋯O, N--H⋯O and C-H⋯O hydrogen bonds. Weak π-π inter-actions involving inversion-related 4-nitro-benzoic acid mol-ecules [centroid-centroid distance = 3.7325 (8) Å] and inversion-related 4-nitro-benzoate mol-ecules [centroid-centroid distance = 3.7124 (8) Å] are also observed.
在标题化合物C(5)H(8)N(3) (+)·C(7)H(4)NO(4) (-)·C(7)H(5)NO(4)中，3,4-二氨基吡啶阳离子的非氢原子共面，最大偏差为0.022 (1) Å。4-硝基苯甲酸根阴离子的羧酸根和硝基分别与相连的环平面扭转成15.89 (8)°和10.20 (8)°的二面角。在4-硝基苯甲酸分子中，羧基和硝基与苯环分别形成18.25 (8)°和6.55 (8)°的二面角。在晶体中，组成单元通过O-H⋯O、N-H⋯O和C-H⋯O氢键形成平行于(001)的二维网络。还观察到涉及反演相关的4-硝基苯甲酸分子[质心-质心距离 = 3.7325 (8) Å]和反演相关的4-硝基苯甲酸根分子[质心-质心距离 = 3.7124 (8) Å]的弱π-π相互作用。
