title: Bis(2,9-dimethyl-1,10-phenanthrolin-1-ium) 2,5-di-carb-oxy-benzene-1,4-di-carb-oxyl-ate-2,9-dimethyl-1,10-phenanthroline-benzene-1,2,4,5-tetra-carb-oxy-lic acid (1/2/1).
abstract: The asymmetric unit of the title co-crystal, 2C14H13N2 (+)·C10H4O8 (2-)·2C14H12N2·C10H6O8, comprises a 2,9-dimethyl-1,10-phenanthrolin-1-ium cation (Me2PhenH(+)) and a 2,9-dimethyl-1,10-phenanthroline mol-ecule (Me2Phen), each in a general position, and half each of a 2,5-di-carb-oxy-benzene-1,4-di-carboxyl-ate dianion (LH2 (2-)) and a benzene-1,2,4,5-tetra-carb-oxy-lic acid mol-ecule (LH4), each being disposed about a centre of inversion. Small twists are evident in the dianion [the C-C-C-O torsion angles are 168.41 (18) and 16.2 (3)°], whereas a major twist is found for one carb-oxy-lic acid group in the neutral mol-ecule [C-C-C-O = 66.3 (2) and 18.2 (3)°]. The most prominent feature of the crystal packing is the formation of linear supra-molecular chains along [001] mediated by charge-assisted O-H⋯O(-) hydrogen bonding between alternating LH4 and LH2 (2-). These are connected to the Me2PhenH(+) and Me2Phen species by N-H⋯O and O-H⋯N hydrogen bonds, respectively. A three-dimensional architecture is formed by C-H⋯O and π-π inter-actions [inter-centroid distance = 3.5337 (17) Å].
authors.affiliation: Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
authors.forename: Hadi D
authors.initials: HD
authors.lastname: Arman
authors.affiliation: Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA.
authors.forename: Trupta
authors.initials: T
authors.lastname: Kaulgud
authors.affiliation: Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Edward R T
authors.initials: ER
authors.lastname: Tiekink