Interfacial Energy and Coherency Strain Energy DFT-Database for Coherent Isostructural Interfaces

Currently, DFT databases are primarily focused on single-phase compounds, yet many industrially relevant materials contain multiple phases. The morphology of these phases, in essence, their microstructure, is crucial for controlling material properties. For instance, the mechanical properties of Al-Cu alloys are regulated by the concentration and morphology of the metastable precipitate Al₂Cu-θ’ and the interfacial interaction with its FCC Al matrix.

Additionally, at low dimensions, like for multiphase nanoparticles, the strain can be naturally present. Either intrinsically, by morphology, or domain structure, or extrinsically, due to lattice mismatch in bimetallic nanoparticles or the interfacial interactions with the supports. The strain can even affect the stability of surface alloys, which are unstable in bulk form. Therefore, to complement and guide experimental investigations and accelerate the discovery of novel phenomena at interfaces, it is essential to take a rational approach toward screening, characterizing, and splitting the different energetic contributions in the interfacial systems.

Here, we present the advances, trends, and correlations found in the development of the first DFT database of Interfacial Energy (IE) and Coherency Strain Energy (CSE) for FCC/FCC, BCC/BCC, and HCP/HCP low-index interfaces ([100],[110],[111], and [0001]). This database contains over 280 coherent isostructural interfaces, which consider all the isostructural combinations in the periodic table that have a size mismatch lower than 20%.