A complete database on the structural and electronic structure properties of Prussian blue, white, and Berlin green is presented. Extensive computational results allow the comparison within the same setups of the geometries, charges, magnetization, band gaps, and other relevant electronic properties. The full theoretical characterization of the compounds indicates that the standard theoretical approaches based on pure density functional theory are not sufficient to accurately retrieve all these properties.
Prussian blue and its related compounds are formed by cheap and abundant metals and have shown their importance in the generation of new fuels by renewable sources. To optimize these compounds it is important to understand their electronic structure and thus establish robust structure–activity relationships. To this end, we employed theoretical simulations based on density functional theory, employing functionals of different degree of complexity, including pure generalized gradient approximation (GGA) and GGA+U functionals, which introduce self-interaction correction terms through the Hubbard parameter, and compared those to the hybrid functionals HSE03 and HSE06. With this robust setup, we can identify an appropriate computational scheme that provides the best compromise between computational demand and accuracy. A complete database considering Berlin green and Prussian blue and white for all alkaline cations is presented.