Dysprosium compounds

Similar dimeric structures are also encountered with bromides. In the case of Gd compound, tetramers have been reported containing two non-equivalent Gd3+ ions with formal coordination numbers of 8 and 9. These tetrameric units form the basic building blocks of compounds like [CpiGdBr] resulting in polymeric infinite double chains. The dysprosium compound [Cp2DyCl]oo has also the polymeric structure. The structure [62] of tetrameric [Cp2GdCIU is shown in Fig. 6.5. 

Glowiak, T., Legendziewicz, I., Dao, C.N., and Huskowska, E. (1991) Absorption, luminescence and crystal structure studies of dysprosium compound with L-a-Alanine [Dy(L-a-AlaH)(H20)6]Q3. Journal of the Less Common Metals, 168 (2), 237-248. 

The lattice parameter of the compounds R3 MC in the lanthanide series for a given element M changes linearly with the radius of the trivalent rare earth ions, following the lanthanide contraction regularity, except for europium and ytterbium which appear to have a variable-valence state. In the ytterbium-M (Al, Ga, In, Tl)-carbon system, the unit cell volume of the compound YbgMC, is larger than the value expected from the relationship mentioned above. In the europium-M(Al, Ga, In, Tl)-carbon system no compound was found. For the compounds of yttrium, as expected, the lattice parameter falls between those of the respective terbium and dysprosium compounds. 

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