Crystal structure of a new complex of [3-(1H-benzimidazol-yl)propionato-N][3-(1H-benzimidazol-yl) propionic acid-N]silver(I), C20H19AgN4O4

The silver and acid hydrogen atoms in the crystal structure of [Ag(pa)(Hpa)]n (Hpa = 3-(1H-benzimidazol-2-yl) propionic acid-N) both lie on special positions of -1 site symmetry; the silver atom shows linear coordination [Ag-N = 2.109(3) Å, N-Ag-N = 180°]. The 'acid hydrogen' links molecules into a linear chain, and hydrogen bonds between the nitrogen-bound hydrogen atom and the carbonyl oxygen atom of an adjacent chain furnish a three-dimensional supramolecular structure. The compound, C20H19AgN4O4, belongs to the triclinic space group P1 [a = 6.536(7), b = 8.127(9), c = 9.051(1) Å; α = 81.692(2),  = 82.819(2),  = 87.229(2)°], and there is one formula unit in the unit cell.