3-Pyridinecarboxylic acid (3-PC) adsorbed on low index face electrodes in NaF solution were investigated using in situ Fourier transform-infrared (MR) spectroscopy and differential capacity measurements. Two types of vertically adsorbed 3-PC were confirmed on the electrodes, while flat-lying adsorbed species were not observed at the potentials measured. At negative potentials, 3-PC molecules adsorb vertically on the electrode via the lone pair electrons of the pyridine ring nitrogen atom, and at positive potentials. 3-PC adsorbs vertically via the two oxygen atoms of the carboxyl group. (C) 2008 Elsevier Ltd. All rights reserved.