Structure-properties relations in Werner β-[Ni(NCS)2(4-MePy)4] clathrates.: part 2.: Host-host interactions as a function of the guest molecular size and shape and the amount of absorbed guest compound

Careful analysis of changes in the geometry of the host lattice structure on inclusion of different guest molecules was performed for 11 beta-[Ni(NCS)(2)(4-methylpyridine)(4)] clathrates reported in the literature, and specific features were established for the geometry of the host crystal lattice structure, which are characteristic for different modes of location of the guest molecules. A new method is suggested for the analysis of the volume and shape of the empty space in clathrates. Experimental data are reported on the dependence of the a and c parameters of the unit cell of clathrate phases (with furan and dichloromethane as guest components) from the guest uptake. Consideration of these data permit us to construct a model of the changes of host-host interactions in the beta-[Ni(NCS)(2)(4-methylpyridine)(4)] clathrates with change of guest uptakes. Modeling of the process of diffusion of the guest molecule through the channel of the beta-[Ni(NCS)(2)(4-methylpyridine)(4)] clathrate allowed the nature of the rate-determining step of diffusion to be established. Part 1 of this series has been published as [3].