Revealing the Underlying Mechanisms of the Stacking Order and Interlayer Magnetism of Bilayer CrBr₃

Aiming to clarify the mechanisms governing interlayer magnetic coupling, we have investigated stacking energy and magnetism of bilayer CrBr3 systemically. The ground states with different R-type H-type orders are established, which found be in good agreement recent experiments [ Science 2019, 366, 983]. Further analyses indicate that is mainly determined by Coulomb interaction between nearest-neighbor Br–Br atoms, while can understood a competition super-superexchange interactions involving t2g–t2g t2g–eg orbitals semicovalent exchange eg–eg orbitals. Our studies give an insightful understanding order CrBr3, should useful understand quantum confinement effect other van der Waals materials.