Crystal structure and Hirshfeld surface analysis of 5-methyl-1,2,4-triazoio[1,5-a]pyrimiame

The nine-membered ring system of the title compound, C6H6N4, is essentially planar. In the crystal, molecules are linked via C-H-Trz center dot center dot center dot N-Trz, and C-H-Pyrm center dot center dot center dot N-Trz (Trz = triazole and Pyrm = pyrimidine) hydrogen bonds together with weaker C-H-Pyrm center dot center dot center dot N(Pyrm )hydrogen bonds to form layers parallel to ((1) over bar 02). The layers are further connected by pi-pi-stacking interactions between the nine-membered ring system [centroid-centroid = 3.7910 (8) angstrom], forming oblique stacks along the a-axis direction. 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 N/N center dot center dot center dot H (40.1%), H center dot center dot center dot H (35.3%), H center dot center dot center dot C/C center dot center dot center dot H (9.5%), N center dot center dot center dot C/C center dot center dot center dot N (9.0%), N center dot center dot center dot N (3.1%) and C center dot center dot center dot C (3.0%) interactions and that hydrogen-bonding and van der Waals interactions are the dominant interactions in the crystal packing. No significant C-H center dot center dot center dot pi interactions are observed.