The chemistry of the actinoids is, on
the other hand, much more complicated The complication arises partly
owing to the occurrence of a wide range of oxidation states in these
elements and partly because their radioactivity creates special problems
in their study; the two series will be considered separately here The names, symbols, electronic configurations of atomic and some
ionic states and atomic and ionic radii of lanthanum and lanthanoids
(for which the general symbol Ln is used) are given in Table 4 9