Hydrothermal synthesis and characterization of novel thorium, uranium, and neptunium solids

Hydrothermal synthesis has been utilized to synthesize several compounds involving thorium, uranium, and neptunium. These compounds have one-, two-, and three-dimensional structural typologies. A majority of the compounds reported are strictly inorganic in composition; however, some examples of solids with the incorporation of organic molecules are reported. The compounds reported consist of thorium(IV) selenites, selenates, chromates, tellurates, and iodates, uranium(VI) periodates, transition metal uranium(IV) fluorides, and neptunium(IV) fluorides. The structural characteristics of these molecules augment the knowledge base of the chemical complexity of these early actinide elements. All structures were delineated through the use of single crystal X-ray diffraction with the aid of EDAX and IR analysis. Structure properties of the synthetic phases were examined as necessary. These structural aspects include second-harmonic generation of light and ion exchange. Examples of open-framework and channel structures are also reported.