Framework contraction in Na-stuffed Si(cF136).
نویسندگان
چکیده
Systematic crystal structure refinements from powder X-ray diffraction data as well as density functional theory calculations demonstrate that the silicon clathrate II Si(cF136) exhibits a lattice contraction as Na is introduced solely into the Si(28) cages. When the Si(20) cages, in addition, begin to be filled with Na, a contrasting lattice expansion results. The nonmonotonic structural response to filling is an indication of markedly dissimilar guest-framework interactions for Na@Si(20) and Na@Si(28).
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عنوان ژورنال:
- Inorganic chemistry
دوره 49 12 شماره
صفحات -
تاریخ انتشار 2010