Literature data on molar excess enthalpies (H-E) and molar excess Gibbs energies (G(E)) of linear alkynes + n-alkanes, cycloalkanes, benzene or tetrachloromethane are treated in the framework of DISQUAC, an extended quasichemical group-contribution theory. The systems are characterized by three types of contact surfaces: acetylenic (Cequivalent toC group), aliphatic (CH3 or CH2 groups), cycloaliphatic (c-CH2 group), aromatic (C6H6 group) and chlorine (CCl4 group). Using a limited number of adjusted contact interchange energies parameters, the model provides a fairly consistent description of the thermodynamic properties as a function of concentration. The model may serve to predict missing data. (C) 2004 Elsevier B.V. All rights reserved.