Crystal structure, Hirshfeld surface analysis and inter-action energy and DFT studies of methyl 4-[3,6-bis-(pyridin-2-yl)pyridazin-4-yl]benzoate.

The title com-pound, CHNO, contains two pyridine rings and one meth-oxy-carbonyl-phenyl group attached to a pyridazine ring which deviates very slightly from planarity. In the crystal, ribbons consisting of inversion-related chains of mol-ecules extending along the -axis direction are formed by C-H⋯O (Mthy = methyl and Carbx = carboxyl-ate) hydrogen bonds. The ribbons are connected into layers parallel to the plane by C-H⋯π(ring) (Bnz = benzene) inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (39.7%), H⋯C/C⋯H (27.5%), H⋯N/N⋯H (15.5%) and O⋯H/H⋯O (11.1%) inter-actions. Hydrogen-bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Computational chemistry indicates that in the crystal, C-H⋯O hydrogen-bond energies are 62.0 and 34.3 kJ mol, respectively. Density functional theory (DFT) optimized structures at the B3LYP/6-311G(d,p) level are com-pared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.