Using density functional theory to study hydrogen diffusion in metals: A brief overview

Density functional theory (DFT) calculations have become a valuable complement to experimental methods for studying the structures and dynamics of H in metal hydrides. This article gives an overview of applications of DFT to the diffusion of H and its isotopes in metals, including pure metals, ordered alloys, and disordered alloys. Several examples are used to illustrate how DFT can be used to predict hopping rates due to activated transport and due to tunnelling using methods that can be applied to large numbers of distinct interstitial sites. The application of DFT to examples where clustering of interstitial H atoms occurs such as Sc is also described.