Interactions of binary mixtures involving some benzene derivatives (ethylbenzene, o-, m-, p-xylene, isopropylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, and methoxybenzene) with benzonitrile were investigated in continuation of our previous studies on binary systems (benzene or toluene + benzonitrile). Heat capacities by volume unit, determined with a Picker flow calorimeter at T=298.15 K, and densities, measured by using Picker vibrating densimeters at the temperatures (298.15 and 308.15) K, are reported. Measurements were made over the entire range of mole fraction. From the primary measurements, the corresponding excess quantities V-E and C-p,m(E) are obtained. The magnitude of these experimental quantities together with H-E literature data is discussed in terms of the nature and type of intermolecular interactions in binary mixtures. (c) 2006 Elsevier Ltd. All rights reserved.