title: 5-Chloro-1H-indole-3-carb-oxy-lic acid.
abstract: In the title compound, C(9)H(6)ClNO(2), the carboxyl group is twisted from the indole ring system by 9.00 (8)°. In the crystal, inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R(2) (2)(8) loops and N-H⋯O hydrogen bonds link the dimers into (001) sheets. Aromatic π-π stacking inter-actions [centroid-centroid distance = 3.7185 (12) A °] are also observed.
authors.affiliation: College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096,  People's Republic of China.
authors.forename: Xue-Lian
authors.initials: XL
authors.lastname: Han
authors.forename: Yang-Hui
authors.initials: YH
authors.lastname: Luo