ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS, vol.75, pp.1672-1684, 2019 (ESCI)
The title compound, C22H16N4O2, contains two pyridine rings and one methoxycarbonylphenyl group attached to a pyridazine ring which deviates very slightly from planarity. In the crystal, ribbons consisting of inversion-related chains of molecules extending along the a-axis direction are formed by C-H-Mthy center dot center dot center dot O-Carbx (Mthy = methyl and Carbx = carboxylate) hydrogen bonds. The ribbons are connected into layers parallel to the bc plane by C-H-Bnz center dot center dot center dot pi(ring) (Bnz = benzene) interactions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H center dot center dot center dot H (39.7%), H center dot center dot center dot C/C center dot center dot center dot H (27.5%), H center dot center dot center dot N/N center dot center dot center dot H (15.5%) and O center dot center dot center dot H/H center dot center dot center dot O (11.1%) interactions. Hydrogen-bonding and van der Waals interactions are the dominant interactions in the crystal packing. Computational chemistry indicates that in the crystal, C-H-Mthy center dot center dot center dot O-Carbx hydrogen-bond energies are 62.0 and 34.3 kJ mol(-1), respectively. Density functional theory (DFT) optimized structures at the B3LYP/6-311G(d,p) level are compared with the experimentally determined molecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.