Delta-lattice-parameter model

Two models are frequently used to predict the activity coefficient of the solid the regular solution model (93) and the DLP (delta-lattice-parameter) model (94). With both models, the activity coefficient of component i, yf, is calculated in terms of the interaction parameter, ft, by the expression... 

We return to the bond fluctuation model on the simple cubic lattice (Sect. 2.2), with a potential for the bond angle (9), and consider [123] the specific choice of parameters N = 20,f = 8.0. For such stiff chains, one is also interested in the global nematic order in the system (in the simulations, L x L x L boxes with L = 90 lattice spacings were used [123]), which is described by the 3x3 order parameter tensor = Kronecker delta) ... 

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