The thermodynamic stability of Xe and CF4 clathrate hydrates has been investigated by evaluating various components of the free energy of formation. Host-guest coupling and lattice distortion are taken into account. It is found that the introduction of CF4 gives rise to a significant distortion of the structure, while Xe does not change the structure from the empty lattice. This distortion, as well as the modulation of the intermolecular vibrational modes of the host lattice, causes an increase in the chemical potential of water. Those contributions, neglected in the traditional theory invariably used to predict phase diagrams, are found to be important for evaluation of the thermodynamic stability of Xe and CF4 hydrates.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry