THE KINETIC-THEORY OF THE ORIENTATIONAL ORDERING PHASE-TRANSITION - THE MODEL AND THE KINETIC-BEHAVIOR

Using a simple microscopic model, the kinetic equations of the orientational ordering phase transition are established and the general characters of the kinetic behavior of the first‐order and the second‐order phase transitions are obtained. The results about the equilibrium state obtained as a special case agree completely with those obtained from the phenomenological theories of the first‐order and the second‐order phase transitions. The different behavior of these two kinds of phase transitions is explained by a unified model. Meanwhile, the relation between them is given and the possibility of a system transiting from one to another caused by external influence is discussed. Lastly, it is shown that in such a non‐equilibrium process, a “potential function” corresponding to the thermodynamic force can be established which is equivalent to the free energy function in the thermodynamics in the equilibrium state and can be used to give the direction and speed of the phase transition in the whole non‐equilibrium process too. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA