A third monoclinic polymorph of 3,4,5-trihy­droxy­benzoic acid monohydrate

The title compound, C(7)H(6)O(5)·H(2)O, is a new polymorph of the structures reported by Jiang et al. (2000 ▶) [Acta Cryst. C56, 594-595] and Okabe et al. (2001 ▶) [Acta Cryst. E57, o764-o766]. The gallic acid mol-ecule is essentially planar (r.m.s. deviation = 0.550 Å). An intra-molecular O-H⋯O hydrogen bond occurs in the gallic acid mol-ecule, which is… CONTINUE READING