The temperature dependences of heat capacity = f ( T ) of fullerene derivatives[(Me
3Si)
3C
60]
2 (I), [(Me
3Si)
7C
60]
2 (II), (Me
3Si)
12С
60 (III) and ( t –Bu)
12C
60 (IV) are compared in the temperature range of 6–635 K. The temperature dependences of heat capacity have been studied by precision adiabatic vacuum calorimetry and differential scanning calorimetry in the ranges of 6.7–350 K and 320–635 K, respectively. In the intervals of 400–466 K and 448–570 K for (I) and (II), respectively, there has been an irreversible endothermic effect caused due to the dimer bond rupture between fullerene fragments and the destruction of the tested fullerene derivatives with heating. The thermodynamic characteristics of this transformation are analyzed. The low-temperature ( T ? 50 K) heat capacity is treated on the basis of the multifractal model. The experimental results for the fullerene derivatives have been used to calculate their standard thermodynamic functions ( Т ), H °( T )– H °(0), S °( T ) and G °( T )– H °(0) in the range from T ? 0 to 448 K and their standard entropies at T = 298.15 K. A comparison of the standard thermodynamic properties of the fullerene derivatives, dimer (C
60)
2 and fullerite C
60 is carried out.
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