Specifics of Actinide Metal Preparation

Specifics of Actinide Metal Preparation A. General Comments 

Differences in the availability and radioactivity of the actinides lead to a great disparity in the lengths of the following discussions of the individual elements. For instance, both thorium and uranium have been 

Although in a strict sense not a member of the actinide series, actinium is included here for completeness as lanthanum is frequently included in the lanthanide series. The longest lived isotope of actinium is with a half-life of 21.8 years. It occurs in nature from the decay 

Actinium decays via a series of short-lived isotopes, eventually ending with stable lead. The presence of these radioactive daughters, particularly Th (which is a strong y-emitter), necessitates the use of lead-lined gloved boxes and remote control manipulators. Consequently, the metallurgy of actinium has been little studied and, due to the great expense and trouble involved, probably will not be studied extensively in the future. 

The first preparation of metallic Ac was on the microgram scale and used the metallothermic reduction (Section II,A) of AcClj with K metal vapor (38), which is the same method used by Klemm and Bommer (67) to prepare La metal. The metal produced by this method is mixed with KCl and K metal. X-Ray diffraction revealed that Ac metal was isostructural with P-La, but that the face-centered cubic cell dimension of Ac (5.311 A) was slightly larger than that of La (5.304 A). 

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