2-Aminonicotinic Acid

2-Amino­nicotinic acid, C₆H₆N₂O₂, crystallized in the centrosymmetric space group P2₁/c in the zwitterionic form. Intermolecular N—H...O hydrogen bonds with N...O distances of 2.652 (2) and 2.807 (2) Å link molecules into two sets of zigzag chains propagating along the b axis. The two sets of chains are crosslinked by C—H...O interactions. The dihedral angle between the planes of adjacent molecules in a chain is 9.77 (7)°. An intramolecular N-H...O hydrogen bond is also present.

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