Synthesis metallothermic reduction

The synthesis of compounds of the lanthanides containing cluster complexes follows in general the same routes as described in The Divalent State in Solid Rare Earth Metal Halides, the conproportionation route and the metallothermic reduction route, for example... 

The separation of the products is not easy, although not impossible. For the exploration of the respective systems and their phase contents, it is, however, often not necessary to obtain pure products because modem, fast X-ray crystallography is an easy means to analyze even multiproduct reactions. Afterward, when the respective compounds are known, care has to be taken to produce the new compounds as pure phase by whatever route is desirable. One major advantage of the metallothermic reduction route is the fairly low reaction temperatures as these allow for the synthesis and crystal growth of compounds that decompose in the solid state, melt incongmently, or even form and decompose in the solid state at fairly low temperatures. Also, low-temperature modifications may be grown as single crystals below the transition temperature. 

Although the berkelium oxidation states, 0 iii, and iv are known in bulk phase, further work is required to characterize more completely the solid-state and solution chemistries of this element. The synthesis of divalent berkelium in bulk should be possible via the metallothermic reduction of its trihalides, e.g. 

A powder with good characteristics (high purity, good homogeneity, fine particle size, narrow particle size distribution, absence of hard agglomerates) is a must to get the desired properties and microstructure in the final component and thus synthesis of high quality powder is extremely important. Powders of ZrB and HfB are synthesized by (a) reaction between elements (Brochu et al., 2008 Tamburini et al., 2008) (b) borothermic reduction of metal oxide (Peshev et al., 1968), (c) boron carbide reduction of metal oxide in presence of carbon (Sonber et al, 2010 2011) (d) carbothermic reduction of metal oxide and B Oj (Fahrenholtz et al., 2007) (e) Metallothermic reduction of metal oxide and B Oj (Setoudeh et al., 2006 Kobayashi et al., 1993),(f) molten salt electrolysis (Frazer et al.,1975) (g) solution based techniques (Yan et al., 2006) and (h) s3mthesis from polymer precursors (Suetal., 1991). 

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