The standard (p(o) = 0.1 MPa) molar enthalpies of formation of the crystalline complexes of dibenzoylmethane (HDBM), thenoyltrifluoroacetone (HTTFA), monothiodibenzoylmethane (HDBMS), and monothiothenoyltrifluoroacetone (HTTFAS) of copper(II) were determined, at T = 298.15 K, by high precision solution-reaction calorimetry. The standard molar enthalpies of sublimation of the copper(II) beta-diketonate complexes were measured by high-temperature Calvet microcalorimetry. From the standard molar enthalpies of formation of the complexes in the gaseous state, the mean molar dissociation enthalpies copper(II)-ligand, (D-m)(Cu-L), were derived. [GRAPHICS] (C) 2005 Elsevier Ltd. All rights reserved.