p-Toluidinium picrate (PTP), is a proton transfer complex of 2,4,6-trinitrophenol as an electron acceptor with p-toluidine as electron donor, crystallizing in the monoclinic system with four molecules in the unit cell (space group P2(1)/c). The vibrational patterns of the organic crystal PTP in comparison with that of the parent compound clearly evidences the complex formation. Loss of hydroxyl proton at O1 leading to specific electron delocalization around C1 is observed. Crystallographic data are reported as a = 12.9304(6) angstrom, b = 15.7176(7) angstrom, c = 7.5403(4) angstrom, beta = 101.837(5)degrees. The crystalline cohesion is achieved by N-H ... O and C-H ... O hydrogen bonds and the ions are linked into three dimensional network. Intermolecular hydrogen bonding between nitrogen of p-toluidine and phenolate ion of picric acid results in charge transfer. A sharp endotherm in the DSC curve, no decomposition up to the melting point and poor absorbance in the visible region indicate the suitability of the material for potential applications. Crown Copyright (c) 2011 Published by Elsevier B.V. All rights reserved.