title: 3-Hy-droxy-pyridinium-2-carboxylate.
abstract: Comparable to many amino acids, the title compound, C(6)H(5)NO(3), is a substitution product of picolinic acid. The mol-ecule shows approximate non-crystallographic C(s) symmetry. Like many amino acids, the mol-ecule is present in its zwitterionic state. Intra- as well as inter-molecular hydrogen bonds are observed, the latter connecting the mol-ecules into zigzag chains along the crystallographic b axis. An inter-molecular C-C distance of only 3.368 (2) Å exclusively involving carbon atoms of aromatic rings (centroid-centroid separation = 3.803 Å) is indicative of π-π inter-actions connecting the mol-ecules into stacks along the crystallographic a axis.
authors.affiliation: Nelson Mandela Metropolitan University, Summerstrand Campus, Department of Chemistry, University Way, Summerstrand, PO Box 77000, Port Elizabeth, 6031,  South Africa.
authors.forename: Richard
authors.initials: R
authors.lastname: Betz
authors.forename: Thomas
authors.initials: T
authors.lastname: Gerber
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