Supra-molecular patterns and Hirshfeld surface analysis in the crystal structure of...

In the title mol-ecular salt, 2C₆H₁₀N₃O⁺·C₈H₄O₄^2-, the N atom of each of the two 2-amino-4-meth-oxy-6-methyl-pyrimidine mol-ecules lying between the amine and methyl groups has been protonated. The dihedral angles between the pyrimidine rings of the cations and the benzene ring of the succinate dianion are 5.04 (8) and 7.95 (8)°. Each of the cations is linked to the anion through a pair of N-H⋯O(carboxyl-ate) hydrogen bonds, forming cyclic R₂²(8) ring motifs which are then linked through inversion-related N-H⋯O hydrogen bonds, giving a central R₂⁴(8) motif. Peripheral amine N-H⋯O hydrogen-bonding inter-actions on either side of the succinate anion, also through centrosymmetric R₂²(8) extensions, form one-dimensional ribbons extending along [211]. The crystal structure also features π-π stacking inter-actions between the aromatic rings of the pyrimidine cations [minimum ring centroid separation = 3.6337 (9) Å]. The inter-molecular inter-actions were also investigated using Hirshfeld surface studies and two-dimensional fingerprint images.