5-Amino-1 H -benzimidazole-2(3 H )-thione: mol-ecular, crystal structure and Hirshfeld surface analysis.

The title compound, C 7 H 7 N 3 S, which has potential biological activity, can be used as a ligand in metal complexation. This compound exists as the thione tautomer in the crystal phase, which is confirmed by the study of its mol-ecular structure. The amino group has pyramidal configuration. In the crystal phase, the two independent mol-ecules in the asymmetric unit form tetra-mers as a result of N-H⋯S hydrogen bonds. These tetra-mers are linked by N-H⋯N hydrogen bonds, forming chains/tubes in the [010] direction. The Hirshfeld surface analysis showed that the highest contribution to the total surface is provided by H⋯H inter-actions as well as S⋯H/H⋯S and C⋯H/H⋯C contacts associated with X -H⋯S hydrogen bonds and X -H⋯C(π) inter-actions.