Uranium diselenide

Uranium Diselenide, Uranous Selenide, UScj, is formed when a current of hydrogen bearing excess of selenium vapour is passed over the double chloride at low red heat or by fusing the same chloride... 

S). Similar compounds with bis(diphenylphoBphino)methane disulfide and the corresponding diselenide have also been prepared (Table X). These are the first examples of coordination of sulfur and selenium donors to actinide pentahalides and it will be interesting to see whether uranium pentahalides behave in a similar fashion since the analogous niobium(V) and tantalum(V) compounds are also known (43). 

The reaction of uranium metal with polyselenides in molten potassium polyselenide generates an interesting molecular diselenide complex K4[U(r/ -Se2)4], containing a discrete U( 7 -Se2)4 anion. 

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