Trans-actinides

Elements 100-103 and the Trans-actinides. The elements 100-103 appear to have the + 3 state, but the + 2 state seems to be more stable than the + 2 state at the end of the lanthanide series. Thus Md3+ is readily reduced to Md2+, and for No the +2 state is the most stable. The last actinide, lawrencium, appears to be most stable in the +3 state (cf. lutetium).54... 

Any discussion of uranium and its chemical properties should refer to the classic 1951 book by Katz and Rabinowitch that was the first publication that provided a comprehensive description of the chemical and physical properties of uranium the element and its binary and related compounds (Katz et al. 1951). More than 60 years later, and despite the considerable developments and extensive research on the chemistry of uranium, this tome is still an excellent primary source. The section on uranium in the series on actinide and trans-actinide chemistry (ATAC) was mentioned earlier as a superb source for understanding the behavior of uranium compounds (Grenthe 2006). A less-known volume that focused on the industrial and technological applications of uranium was translated from Russian in the 1960s and also is useful (although somewhat outdated in parts) for following the production processes of uranium (Galkin 1966). 

The actinides uranium and thorium occur in nature as primordial matter. Actinium and protactinium occur in nature as daughters of thorium and uranium, while small amounts of neptunium and plutonium are present as a result of neutron-capture reactions of uranium. All other members of the series are man-made. Separation chemistry has been central to the isolation and purification of the actinides since their discovery. The formation of the transplutonium actinides was established only as a result of chemical-separation procedures developed specifically for that purpose. The continued application of separation science has resulted in the availability of weighable quantities of the actinides to fermium. Separation procedures are central to one-atom-at-a-time chemistry used to identify synthetic trans-actinide (superheavy) elements to element 107 and above (Report of a Workshop on Transactinium Science 1990). 

Leino, M., Hessberger, F.P. The nuclear structure of heavy-actinide and trans actinide nuclei. Ann. Rev. Nucl. Part. Sci. 54, 175-215 (2004)... 

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