title: A 2:1 co-crystal of p-nitro-benzoic acid and N,N'-bis-(pyridin-3-ylmeth-yl)ethanedi-amide: crystal structure and Hirshfeld surface analysis.
abstract: The title 2:1 co-crystal, 2C7H5NO4·C14H14N4O2, in which the complete di-amide mol-ecule is generated by crystallographic inversion symmetry, features a three-mol-ecule aggregate sustained by hydroxyl-O-H⋯N(pyrid-yl) hydrogen bonds. The p-nitro-benzoic acid mol-ecule is non-planar, exhibiting twists of both the carb-oxy-lic acid and nitro groups, which form dihedral angles of 10.16 (9) and 4.24 (4)°, respectively, with the benzene ring. The di-amide mol-ecule has a conformation approximating to a Z shape, with the pyridyl rings lying to either side of the central, almost planar di-amide residue (r.m.s. deviation of the eight atoms being 0.025 Å), and forming dihedral angles of 77.22 (6)° with it. In the crystal, three-mol-ecule aggregates are linked into a linear supra-molecular ladder sustained by amide-N-H⋯O(nitro) hydrogen bonds and orientated along [10-4]. The ladders are connected into a double layer via pyridyl- and benzene-C-H⋯O(amide) inter-actions, which, in turn, are connected into a three-dimensional architecture via π-π stacking inter-actions between pyridyl and benzene rings [inter-centroid distance = 3.6947 (8) Å]. An evaluation of the Hirshfeld surfaces confirm the importance of inter-molecular inter-actions involving oxygen atoms as well as the π-π inter-actions.
authors: Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors: Sabrina
authors: S
authors: Syed
authors: Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors: Siti Nadiah Abdul
authors: SN
authors: Halim
authors: Department of Physics, Bhavan's Sheth R. A. College of Science, Ahmedabad, Gujarat 380001, India.
authors: Mukesh M
authors: MM
authors: Jotani
authors: Centre for Crystalline Materials, Faculty of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia.
authors: Edward R T
authors: ER
authors: Tiekink
keywords: Hirshfeld surface analysis; carb­oxy­lic acid; co-crystal; crystal structure; hydrogen bonding; thio­amide