Metal containing materials, cubic phases

It is now certain that metal carboxylates were the first metal-containing liquid crystals, reported in 1855 with Heinz s work on magnesium tetradecanoate. Then, many other mesomorphic mono-, di-, and tri-valent carboxylate complexes, with the general formula [M(02CC H2 +i)J (x=l, 2, 3) or [M2(02CC H2 +i)4] were prepared. Some of them were described in 1910 by Vorlander." These materials may show thermotropic nematic, smectic, cubic, and columnar mesophases, but also, when dissolved in water or alkanes, lyotropic mesophases. While not all of the compounds described in this section show columnar phases, it was decided to keep these materials together. 

The doping of Zr02 with alkaline earth metal cations (A ) is less effective due to a greater tendency to defect association and to a lower thermodynamic stability of the cubic fluorite-type solid solutions in Zr02-A0 systems. To date, attempts to increase the stability of Sc-containing materials by codoping, or to reduce the cost of Ln -stabilized phases by mixing them with cheaper alkaline earth dopants, have not yielded any worthwhile results [228]. 

Owing to the sizable Zr Ql, the bulk of Zr zero-field NMR and early field-swept NMR studies focused on Zr-containing metals as well as Laves- and pseudo-Laves-phase compounds, which typically feature Zr centers in environments of exceptionally high spherical symmetry (i.e., cubic) and are associated with near-zero Zr QIs. Laves-phase compounds are intermetaUic materials composed of rare earth metals and 3d transition metals which have peculiar properties, such as stoichiometric and/or... 

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