THERMODYNAMIC PROPERTIES OF IMPERFECT SOLIDS NEAR FREEZING POINT

摘要

Using a classical density functional approach a model for the metastable liquid sate in terms of holes present in the amorphous structure is considered. A temperature T_o, similar to that of the characteristic transition of the free volume theory, is identified. The Kauzmann temperature T_K is also obtained from extrapolation of the entropy difference between the supercooled state and that of the crystal to zero. Applying the similar approach for the crystalline solid, we include in the classical density functional description of the crystal the effects due to the distortion of the lattice structure surrounding the vacancy. The test density function is modified from its usual form to take into account the presence of vacancies in the lattice structure. The thermodynamic behavior is studied by locating the state of minimum free energy.