Vapour pressures and molar enthalpies of vaporization of a series of delta-lactones delta-valerolactone (CAS#542-28-9), delta-hexanolactone (CAS#823-22-3), delta-octanolactone (CAS#698-76-0), delta-nonanolactone (CAS#3301-94-8), and delta-decanolactone (CAS#705-86-2)) have been determined by the transpiration method. A linear correlation of enthalpies of vaporization Delta H-g(1)m at T = 298.15 K of the delta-lactones studied with the number of carbon atoms has been found. (c) 2006 Elsevier Ltd. All rights reserved.