Crystal structure, Hirshfeld surface analysis, calculations of inter-molecular inter-action energies and energy frameworks and the DFT-optimized mol-ecular structure of 1-[(1-butyl-1 H -1,2,3-triazol-4-yl)meth-yl]-3-(prop-1-en-2-yl)-1 H -benzimidazol-2-one.

The benzimidazole entity of the title mol-ecule, C 17 H 21 N 5 O, is almost planar (r.m.s. deviation = 0.0262 Å). In the crystal, bifurcated C-H⋯O hydrogen bonds link individual mol-ecules into layers extending parallel to the ac plane. Two weak C-H⋯π(ring) inter-actions may also be effective in the stabilization of the crystal structure. Hirshfeld surface analysis of the crystal structure reveals that the most important contributions for the crystal packing are from H⋯H (57.9%), H⋯C/C⋯H (18.1%) and H⋯O/O⋯H (14.9%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the most dominant forces in the crystal packing. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization of the title compound is dominated via dispersion energy contributions. The mol-ecular structure optimized by density functional theory (DFT) at the B3LYP/6-311 G(d,p) level is compared with the experimentally determined mol-ecular structure in the solid state.