Crystal disintegration

A few dense crystals heated with sulfuric acid exploded, owing to the exotherm in contact with water liberated as the crystals disintegrated. 

Dimerization and other topochemical photoreactions in the solid state occur heterogeneously—with the crystal disintegrating as the photoproduct is generated in... 

Figure 22. Polymorphic transition with respect to NNMe3 in a case where an odd number (three in this case) of homochiral R chains are surrounded by two S chains in the y-form crystal, leading to the fairly ordered 8-form crystal without crystal disintegration.

Figure 26. Mechanism of Preferential Enrichment characterized by homochiral molecular association, polymorphic transition, followed by crystal disintegration, and chiral discrimination in the case of NNMe,. (Reprinted with permission from ref 18. Copyright 2003 American Chemical Society.)...

The conformations of the four peptide molecules are found to be nearly identical except for some very minor variations in the orientations of the valine and leucine side chains, as shown in Figure 15.10. This indicates the variability of conformation in this crystal. Toluene molecules are distributed in channels throughout the crystal and the methanol molecules are encapsulated in small holes in the crystal structure. Upon standing in air, the crystals disintegrate, probably as a result of loss of solvent of crystallization. The association of peptide molecules with toluene and methanol appears necessary to achieve a stable packing arrangement. Studies of this dolastatin 3 analogue in solution also supports this interpretation. ... 

Formula weight 5706.59. The colored crystals disintegrate, often even in a few hours, to a crystalline powder the colorless... 

UBi. No new results are known since the ones discussed by Lam and Aldred (1974) and Kuznietz et al. (1968). This is probably due to the fact that UBi is very unstable, even if protected from air, Single crystals disintegrate within a short time. 

Crystal structure. The crystalline complexes (tt-CsHs) —, —V, —Cr, —Fe, —Co, —Ni, are isomorphous and have a monoclinic form [57]. On rapid cooling of crystalline ferrocene the crystals disintegrate fairly violently to a powder. Studies on the heat capacity of ferrocene have shown that there is a A point transition at 163 9°K the A range is about 125-200 K [58]. 

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