Crystal expansion

The direct evidence that Besenhard et al. presented for the formation of a ternary GIC is the dilatometric measurement of the graphite electrode, which indicates a crystal expansion of 150% at the cointercalation potential. However, this expansion due to solvent cointercalation was never confirmed on the microscopic level. All of the in situ X-ray diffraction (XRD) measurements conducted by different research-... 

The absence of initial contraction in zeolite 8 Li-4 NaA is probably caused by the fact that Li+ cations may be situated in other positions inside the voids because of their small sizes. This is corroborated by the fact that Li exchange increases the lattice parameter a of zeolite LiA by 2.6% compared with zeolite NaA. Then, the same processes occur as in NaA, leading to crystal expansion. Perhaps at high fillings Li cations extend from six-membered oxygen windows into the large voids this would decrease the contraction of their positive charges and expand the crystal lattice. 

Crystal Expansion coefficient a (JO-6 jj-1) Remarks Temperature dependence... 

Crystal Expansion coefficient a (10- K-1) Temperature (K) Temperature dependence Remarks... 

At 373K < T < 873K, swelling of BeO should be attributed only to lattice defect growth (anisotropic crystal expansion) and microcracking. 

The anisotropic BeO crystal structure leads to anisotropic crystal expansion of BeO and microcracking. 

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