High quality epitaxial thin films of actinide oxides, carbides, and nitrides: Advancing understanding of electronic structure of f-element materials

• Synthesis of epitaxial thin films of actinide oxide, carbide, and nitrides is reviewed.
• Electronic structure data including ARPES and optical band gaps is presented.
• Hybrid DFT models are validated and understanding of f-electron behavior is advanced.
• Potential applications in nuclear energy and environmental fate of the actinides.

Over the past five years we have developed a solution based technique for synthesizing high quality epitaxial thin films of actinide materials. These films include oxides (UO2, U3O8, PuO2, and NpO2), UC2, UN2, UC2−xOx, and UN2−xOx. These nearly single crystal quality films have allowed unprecedented experimental measurements (ARPES, optical band gap, electrical conductivity, and XRD). These data have bench marked and advanced DFT theoretical predictions and understanding of bonding and electronic structure in f-orbital actinide materials. The synthesis and characterization of the films, measurement of electronic structure, and the resulting validation of theoretical models are reviewed. The potential impacts of this work in areas ranging from nuclear energy to environmental fate of actinides in the environment are discussed.