Configurations ordering

Let us therefore assume that a preliminary full SDT[N/M]-C1 calculation is made. We then examine the triply excited configurations, order them by space... 

Most chemical reactions occur by a change in the configurational order (AS 0). Compared to fluids, crystalline reactants already have a low entropy and thus solid state reactions are normally exothermic In this sense, order-disorder reactions are in no way special, except that they occur in homophase crystals. 

What this equation tells us is to find all N clusters of type a and to evaluate the product CT1CT2 a for each such cluster and to add up the contributions from them all. In the particular case written above, our notation has been chosen such that there are n sites involved in the a cluster type. The entirety of these averaged correlation functions provides a measure of the configurational order associated with the structure of interest. What these equations tell us physically is that the energetics is expanded in terms of various correlation functions that characterize the extent to which adjacent atoms are like or unlike. 

Configuration Order of states0 State Direct Hss Isoconfigurational second-order Hso SS xalc. AlS,c.(iso) eff /vexD. 

Another saturated hydrocarbon polymer that has been studied is polypropylene . The isotactic form (with the methyl groups on one side of the chain) crystallizes the atactic form has insufficient configurational order for crystallization. It has been shown that in relatively highly crystalline isotactic material G(sc)/G(cl) 1.5 —1.8, while in material with low crystallinity (atactic as well as isotactic) a value of ca 0.8 is found. 

Following the same line of thoughts, it is possible to define a configurational order parameter, P2)ci which tends to one for a configuration perfectly ordered according to the idealized structmre induced by the boundary conditions used ... 

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