Extended Hubbard modelling of metal-organic-frameworks

Metal-organic frameworks (MOFs) are porous materials composed of metal ions and organic linkers. They support a range of applications, such as gas storage, and their compositions can be optimized through computational modeling. Numerous studies have used density-functional theory (DFT) for investigating MOFs, often supplemented with corrections that account for strong electronic correlations. The Hubbard U correction is typically used to treat localized electrons, thus improving band gap predictions. Although U is often estimated empirically, it can be derived from first-principles calculations. In addition, the extended Hubbard model introduces the V parameter that captures inter-site interactions, accounting for hybridization effects. However, the application of the DFT+U+V approach to MOFs remains largely unexplored. In this work, we have selected a set of MOFs for computing both U and V parameters using the Quantum Espresso code. The simulation results are compiled into a representative dataset, allowing for investigating Hubbard parameter correlations across a variety of MOFs. Importantly, we have explored the correlations between Hubbard parameters and MOF properties, such as the band gap. Our result provides insights for advancing future MOF applications.