Intercrystalline free space

It should be noted that solid explosives may be detonated in any condition from a coarse powder to a single crystal (Ref 6, p 166). Heterogeneous polycrystalline mixtures can be termed "solid only by convention phenomena such as grain erosion in the detonation reaction zone are of dominant importance. They depend in a complex way on the intercrystalline free space and on a free space more strictly defined, the difference between the volume of the crystals and the volume of the ions therein... 

For molecular mean free paths much less than the mean free diameters of the intercrystalline void space in the zeolite bed, Din, is controlled by the same mechanism as in the gas phase, with a self-diffusion coefficient Dg. Due to the steric confinement, Dimer is reduced with respect to Dg by a tortuosity factor, Tb, with values typically of the order of 2-3. The mean free path can be estimated through the relation... 

Effective mean free path in the intercrystalline space Tortuosity factor Intracrystalline mean life time... 

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