3-Hy­droxy­pyridinium-2-carboxylate

Comparable to many amino acids, the title compound, C(6)H(5)NO(3), is a substitution product of picolinic acid. The mol­ecule shows approximate non-crystallographic C(s) symmetry. Like many amino acids, the mol­ecule is present in its zwitterionic state. Intra- as well as inter­molecular hydrogen bonds are observed, the latter connecting the mol­ecules into zigzag chains along the crystallographic b axis. An inter­molecular 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 inter­actions connecting the mol­ecules into stacks along the crystallographic a axis.