The densities for binary mixtures of dichloromethane with aniline, or nitrobenzene, respectively, including those of pure liquids, were measured over the entire composition range at T = (288.15, 293.15, 298.15, and 303.15) K and atmospheric pressure using a vibrating-tube densimeter. From the experimental results, the excess molar volumes, V-m(E), partial molar volumes, (V) over bar (i), the apparent molar volume, V-Phi i, and the partial molar excess Volumes at infinite dilution, ((V) over bar (E)(i))(infinity), were calculated over whole composition range. Negative values of V-m(E) for (dichloromethane + aniline) attributed to the formation of the charge transfer complex, while for (dichloromethane + nitrobenzene) system, the free Volume effect played a dominant role. The extent of negative deviations in V-m(E) values follows the order: nitrobenzene > aniline. The Prigogine-Flory-Patterson (PFP) theory and its applicability in predicting VE at T = 298.15 K were tested. There is a good agreement in general between the experimental V-m(E) values and those predicted by PFP theory. (c) 2008 Elsevier Ltd. All rights reserved.