Physics

Symmetry (geometry)

Mathematics

Crystallography

Density functional theory

Paramagnetism

Perovskite (structure)

Catalysis

Computational chemistry

Band gap

Chemical physics

Disproportionation

Chemistry

Materials science

Geometry

Condensed matter physics

Quantum mechanics

Ground state

Biochemistry

Nature Communications

With their broad range of properties, ABO 3 transition metal perovskite oxides have long served as a platform for device applications and as a testing bed for different condensed matter theories. Their insulating character and structural distortions are often ascribed to dynamical electronic correlations within a universal, symmetry-conserving paradigm. This view restricts predictive theory to complex computational schemes, going beyond density functional theory (DFT). Here, we show that, if one allows symmetry-breaking energy-lowering crystal symmetry reductions and electronic instabilities within DFT, one successfully and systematically recovers the trends in the observed band gaps, magnetic moments, type of magnetic and crystallographic ground state, bond disproportionation and ligand hole effects, Mott vs. charge transfer insulator behaviors, and the amplitude of structural deformation modes including Jahn-Teller in low temperature spin-ordered and high temperature disordered paramagnetic phases. We then provide a classification of the four mechanisms of gap formation and establish DFT as a reliable base platform to study the ground state properties in complex oxides.

Origin of band gaps in 3d perovskite oxides