Chemistry of Americium and Subsequent Actinides

Americium undergoes slow oxidation in air and dissolves in dil. HCl, as expected from its favourable potential [ (Am/Am +) = —2.07 V]. 

The tendency noted for plutonium for disproportionation occurs here, as both and Am tend to disproportionate in solution  

There is also again the tendency to autoradiolysis, the reduction of high oxidation states through the effects of the a-radiation emitted. 

Relatively few complexes of americium have been characterized those that have tend to resemble the corresponding compounds of the three previous metals. Many are halide complexes, such as (NH4)4 [AmFg], which resembles the U analogue, Cs2NaAmCl6, and (Ph3PH)3AmX6 (X = Cl, Br). 

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