Growth of deuterated hydrogen uranyl phosphate tetrahydrate single crystals

Single crystals of hydrogen uranyl phosphate tetrahydrate were grown from a sodium silicate gel prepared from deuterated materials. The starting materials were anhydrous sodium metasilicate, Na2SiO3, deuterated H3PO4, deuterium oxide and uranyl nitrate hexahydrate. The uranyl salt was first dehydrated and then deuterated by on of two experimental procedures. A gel was prepared from the silicate and phosphoric acid and the uranyl salt added once the gel had set firm. As diffusion of the uranyl ion proceeded, clusters of microcrystalline (deuterated) hydrogen uranyl phosphate (DUP) began to appear. The crystals were clear, yellow and square, identical in appearance to the hydrogen material previously grown by this method. The largest of the crystals was 0.25 mm on an edge and 0.10 mm thick. An x-ray determination showed the material to the Type I HUP. Since HUP is protonic conductor, a comparison of the deuterated versus the hydrogen conductivity would prove interesting