Einsteinium species

In all samples prepared in which the oxidation state of the einsteinium differed from that of the host cation, over a time period of several years, only californium(III) has been identified as arising from the samples that initially contained einsteinium (III), and only californium(II) has been observed in samples that originally contained einsteinium(II). Even when the parent was in a host of differing oxidation state, the progeny species maintained the oxidation state of the parent ... 

All the solid actinide monoxides which have been reported are now believed to have been oxynitrides, oxycarbides, or hydrides. The highest potential for existence would have the monoxides for the divalent actinide metals einsteinium through nobelium. Only the gaseous monoxides are well-established species. All actinides are known or expected to form gaseous monoxides. 

It is quite possible that nature can accomplish this synthesis through alpha decay of the dihalides of einsteinium-253. A direct synthesis would allow both absorption spectrophotometric and x-ray powder diffraction analyses, the results of which would aid in the identification of Bk(ii) species in aged einsteinium dihalide samples which also contain Cf(ii) [110,236]. 

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