his proposal is for the continuation of the current project: Atomic scale studies of physical-chemical properties of metallic materials for energy applications (SNIC 2022-5-545). This project includes the research topics. 1) A large effort is being put in the study of physical-chemical properties of copper as a containment barrier for the Swedish repository for spent nuclear fuel: the study of reactions with water and sulfide and hydrogenation of the surfaces and bulk copper; studies of the structure of grain boundaries in bulk copper and if impurities can accumulate at those sites and affect the materials performance. These studies are essential for the safety assessment of the containment barriers for spent nuclear fuel in the Swedish repository. 2) The relative stability of carbides and nitrides of actinide elements is studied in the context of the development of the fuels for generation IV reactors. Studies of their surfaces will be conducted in 2024. 3) Semiconductor catalysts for light drive catalysis. The surfaces and structural properties of these materials will be studied for harvesting light and driving chemical reactions that can be used to convert water and biomass molecules to hydrogen. 4) Structural features of energy materials. This topic includes the computation of large sets of data with DFT. This data is then used in structural analyses methods that can describe symmetry of atomic sites. This information is essential for the rational design of the materials. These studies involve accurate investigations of the chemical bonding in the systems. To have more accurate data these investigations have to make use of large supercells to account for defects and other low symmetry structural features of the systems. These investigations will use quantum mechanical modelling at the density functional theory (DFT) and wave function levels of theory. This to study the mechanisms and the physical-chemical properties behind chemical reactivity of these technologically relevant materials towards chemical species that are responsible for affecting their performance, and also, processes such as corrosion, wearing and other structural modifications that lead to poor performance of the materials. The results obtained will be directly employed by other scientists that have as goal understanding and improving the materials performance. Overall, the project SNIC 2022-5-545 has generated important data that resulted in important reports and in several papers and several manuscripts submitted for publication and in preparation-please see the project report. The research conducted with PDC resources has been essential for the safety assessment of the Swedish repository for spent nuclear fuel and in recent years several of our papers that used the PDC machine have been featured as journal covers and are often used by "mark och miljödomstolen", SSM and other public authorities to make decisions on the repository. The continuation of this research is essential for the safety assessment of the repository.