Crystal structure of 1,10-phenanthrolinium violurate violuric acid pentahydrate

Abstract

The title compound [systematic name: 1,10-phenanthrolinium 6-hydroxy-5-(oxidoimino)-1,3-diazinane-2,4-dione–6-hydroxy-5-(hydroxyimino)-1,3-diazinane-2,4-dione–water (1/1/5)], C12H9N2+·C4H2N3O4−·C4H3N3O4·5H2O, is a co-crystal salt hydrate comprising 1,10-phenanthrolinium cations, violurate anions, free violuric acid as co-former and five water molecules of crystallization per formula unit. The violurate and the violuric acid residues each form distinct N—H...O hydrogen-bonded tapes with a common R22(8) hydrogen-bond motif extending parallel to (103). Solvent water molecules connect the tapes to form a tri-periodic hydrogen-bonded network with channels extending parallel to the a-axis direction, which accommodate the N—H...Owater hydrogen-bonded 1,10-phenanthrolinium cations. Direct N—H...O hydrogen bonds between the 1,10-phenanthrolinium and violurate ions are not encountered.

Keywords

• 1,10-phenanthroline
• violuric acid
• proton-transfer compound
• hydrogen bonding
• co-crystal
• crystal structure