Reexamination of Uranium (IV) Phosphate Chemistry

Abstract During the past 40 years, few papers concerning uranium (IV) phosphate chemistry have been cited as references in usual textbooks and nobody, up to now, has questioned their veracity. In our recent studies on uranium (IV) phosphates, we found that some of them, like U 3 (PO 4 ) 4 , do not exist or, like (U 2 O 3 )P 2 O 7 , were wrongly identified. Thus, the reinvestigation of uranium (IV) phosphates was decided to be necessary. Some new compounds were prepared and identified. From previously published results, this paper draws up a balance sheet of the scope concerning the complete understanding of the chemistry of tetravalent uranium phosphates. This new approach is given in terms of a survey of the literature errors to set the facts in their true light. Two synoptic schemes are given to bring forward evidence of new compounds, U(UO 2 )(PO 4 ) 2 and U 2 O(PO 4 ) 2 , which appear to be significant in the chemistry of uranium (IV) phosphates.