Crystallite model

Roe, R. J., K. J. Smith jr., and W. Krigbaum Equilibrium degrees of crystallisation predicted for "single pass" and folded chain crystallite models. J. Chem. Phys. 35, 1306-1311 (1961). 

Considerable efforts have been made over the years to discover if specific activity (and, where relevant, selectivity) are dependent on the size of the metal crystallites in a supported catalyst, which might be anticipated for several reasons. With use of regular shapes, such as the cubo-octahedron, as crystallite models the fractions of surface atoms with various co-ordination numbers can be calculated as a function of crystaUite size and show marked variation in the size range below The statistics of surface atoms and... 

What is a fringed micelle or a fringed crystallite model ... 

Recent quantitative calculations of the absolute scattering intensities expected from various crystallite models for single crystals by Keller (121) and Yoon and Flory (125-127) (Figure 6.34) on polyethylene suggested that the model for adjacent reentry does not correlate with experiment. Rather, Yoon and Flory put forward a model requiring a stem dilution by a factor of 2-3. The calculated scattering functions are shown in Figure 6.34 this leads to the... 

Equations (18) and (19) represent the dependence of the equilibrium melting temperature on chain length for a pure polymer system which adheres to the crystallite model of Figure 14. Here dg represents the interfacial free energy associated with the basal plane of the equilibrium crystallite. Tjn g is the equilibrium melting temperature of a crystallite of size Ce which is comprised of chains of x units. It should not be identified a priori with the melting temperature of a molecular crystal formed by chains of the same size. Equation (18) can be rewritten in more compact form as... 

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