title: 2-Hydr-oxy-3-methoxy-benzoic acid monohydrate.
abstract: The asymmetric unit of the title compound, C(8)H(8)O(4)·H(2)O, contains two organic mol-ecules which are connected by the two water mol-ecules through O-H⋯O hydrogen bonds, forming an R(4) (4)(12) ring. Further O-H⋯O hydrogen bonds assemble these rings through R(6) (6)(18) rings, giving rise to infinite helical chains arranged around the b axis. These helical chains are assembled by offset π-π stacking inter-actions [centroid-centroid distance = 3.6432 (8) Å] between the aromatic rings of neigboring chains, forming a supra-molecular network.
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.
authors.forename: Zhan-Qiang
authors.initials: ZQ
authors.lastname: Fang
authors.forename: Rong-Hua
authors.initials: RH
authors.lastname: Zeng
authors.forename: Mei
authors.initials: M
authors.lastname: Yang
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.forename: Xiao-Lei
authors.initials: XL
authors.lastname: Chen