Unusual hexamers and infinite water chains trapped in the complexes of 2-(4-pyridyl)benzimidazole

Abstract

Unusual hexamers and water chains have been observed in the complexes of (HPyBIm) + (Hterephate) − (PyBIm) · 4H 2O ( 1) and [Ag 2(PyBIm) 2(μ 2-SO 4)] · 4H 2O ( 2), respectively (PyBIm = 2-(4-pyridyl)benzimidazole). In 1, a chair-shaped hexamer (not water hexamer) formed by the water molecules and carboxylate groups as well as one-dimensional water chain are being observed. While in 2, a water hexamer-shaped as parallelogram is obtained; more interestingly, the parallelogram-shaped water hexamers are further aggregated into tape like infinite water chain via hydrogen-bonding interactions.