jats:sec<jats:label />jats:pThe electronic structure, vacancy symmetry, defect levels, ferroelectric phases, and interface properties of HfOjats:sub2</jats:sub> are studied using a GGA + jats:italicU</jats:italic>(jats:italicd,p</jats:italic>) approach, a simplified version of the ACBN0 method. Introducing an on‐site Coulomb interaction to both Hf 5jats:italicd</jats:italic> orbitals and O 2jats:italicp</jats:italic> orbitals reproduces the experimental bandgap, gives band energies similar to those of hybrid functionals, gives the correct symmetry for the oxygen vacancy, and describes the Schottky barriers at the metallic contacts like TiN correctly. The energetics of phase energies and strain arising from different ferroelectric–electrode interfaces are tested. The GGA + jats:italicU</jats:italic>(jats:italicd,p</jats:italic>) approach is a useful tool to study various HfOjats:sub2</jats:sub> configurations by rapid ab initio molecular dynamics calculations.</jats:p></jats:sec>