In the present work, firstly the temperature dependence of heat capacity C degrees(p.m) = f (T) of the crystalline fullerene complex [(Me3Si)(3)C-60](2) has been measured between T = (6 and 350) K and T = (330 and 480) K by precision adiabatic vacuum and dynamic calorimetry, respectively. The irreversible endothermic effect was detected in the temperature range from T = (400 to 466) K and its thermodynamic characteristics have been determined and analysed. This transformation was caused by the opening of a dimeric bond between fullerene fragments and the decomposition of the tested complex on heating. The experimental data were used for calculating the standard (p degrees =0.1 MPa) thermodynamic functions C degrees(p.m)/R, Delta H-T(0)degrees(m)/RT, Delta S-T(0)degrees(m)/R and Phi degrees(m) /R = Delta S-T(0)degrees(m)/R - Delta H-T(0)degrees(m)/RT (where R is gas constant) in the range 0 <= T/K <= 400. The value of the standard entropy of formation of the complex from simple substances at T=298.15 K has been estimated. (C) 2006 Elsevier Ltd. All rights reserved.