High temperature vaporization and thermodynamic properties of the potassium -: C60 phases

Knudsen cell mass spectrometry and simultaneous Knudsen-torsion effusion technique were used to study K/C-60 binary system. Activities of potassium and/or C-60 were measured in all heterogeneous regions of the K-C-60 phase diagram and the Gibbs energies of formation of KxC60 (x=1,3,4,6) were calculated. Gaseous species KC60(g) was identified and the Gibbs energy of formation of KC60(g) was calculated directly from the experimental data.