The crystal structure of nicotinic acid

Abstract

The crystal structure of nicotinic acid has been determined by two-and three-dimensional X-ray methods. The bond lengths, which have a probable error of 0.014 A, are: pyridine ring C-C = 1-38 A, C-N =-1-34 A, carboxyl group C~-C e --1.48 A, C-O 1 --1.34 A, C6-O 2 = 1-18 A. The molecules are linked in chains parallel to the b axis by hydrogen bonds of length 2.66 A between O1 and the nitrogen atom of the next molecule.