A modification incorporating the distortion of the host lattice by the
guest molecule, for van der Waals and Plateeuw's Thermodynamic model
for prediction of hydrate equilibrium is suggested. The impact of the
guest molecule on the interaction energy and hence the stability of th
e lattice is studied, Improved equilibrium prediction is achieved by c
onsidering the perturbation effect by the guest molecule on the host l
attice.