REEXAMINATION OF URANIUM(IV) PHOSPHATE CHEMISTRY

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 u ranium (IV) phosphates, we found that some of them, like U-3(PO4)(4), do not exist or, like (U2O3)P2O7, were wrongly identified. Thus, the r einvestigation of uranium (IV) phosphates was decided to be necessary. Some new compounds were prepared and identified. From previously publ ished results, this paper draws up a balance sheet of the scope concer ning the complete understanding of the chemistry of tetravalent uraniu m phosphates. This new approach is given in terms of a survey of the l iterature errors to set the facts in their true light. Two synoptic sc hemes are given to bring forward evidence of new compounds, U(UO2)(PO4 )(2) and U2O(PO4)(2), which appear to be significant in the chemistry of uranium (IV) phosphates. (C) 1996 Academic Press, Inc.