Minimal free energy, equilibrium phase diagram

If the phase separation is possible, the free energy of phase separation is negative and characterized by a deep minimum. Because of this the unknown variables of the equation, which are necessary for constructing phase diagrams, may be found by minimization of the fimction Agpg. This term, as distinct from the free energy of mixing, allows in the closed form the condition of the phase equilibrium (bimodal equation) to be recorded for... 

The translationally ordered state characteristic of crystallites that are large with respect to the wavelengths of X-rays represents perfect phases in the sense of thermodynamics, to which phase diagrams apply. Even this idealized state of matter cannot exist without deviations from perfect ordering, however, because of a requirement of thermodynamics (the entropy of the material at equilibrium must be nonzero for the Gibbs free energy to be minimized). Thus, the material will contain a number of deviations from the ideal arrangement, called defects."... 

Calculations of the equilibrium conditions under which CVD of boron carbide from BCI3-CH4-H2 mixtures takes place consider the partial pressures of the gaseous species present. The method minimizes the free energy and the theoretical diagrams are compared to experimental observations . Mass-transfer and diffusion kinetics in the gas phase are related to the morphology and composition of the deposits " . 

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