The Actinoid Metals

Longest-lived isotope Half-Ufe Decay mode 

Longest-lived Half-life Decay mode Longest-Uved Half-Ufe Decay mode 

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Among the actinoid metals, Am, Cf, and Es have properties sufficiently similar to the volatile lanthanoids that they can be prepared according to reaction (d) . Substitution of less volatile Th for La allows this method to be used for the reduction of Ac, Pu, and Cm. 

The actinoid can thus be reduced with hydrogen to form an alloy. In a subsequent step the actinoid metal is purified from the alloy by fractional sublimation ... 

All the actinoid metals can be prepared by reducing their carbides with Ta Carbides are prepared from oxides [reaction (a)] at 2000°C with graphite in vacuum, and the actinoid metals (except for Th and Pa) are purified from Ta and TaC by distillation. 

Alkyl derivatives are more stable if the actinoid metal is also bound to cyclopentadienyl ligands and reactions 24.44-24.46 show general methods of synthesis where M = Th or U. 

G.T. Seaborg, J.J. Katz and L.R. Moss (1986) The Chemistry of the Actinide Elements, 2nd edn, Kluwer, Dordrecht - An excellent account of the actinoid metals. 

A major change from previous editions of Inorganic Chemistry is the removal of the detailed discussion of nuclear chemistiy. This decision was not made lightly, but came after consideration of comments from the review panel set up by the publisher and from discussions with a number of colleagues. A proportiiMi of the material still appears in the text. For example, an introduction to decay chains is now described with the actinoid metals in Chapter 27. 

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