First principles calculations of ideal and defected BiMnO3

Presented calculations were designed to evaluate the impact of point defects on the macroscopic properties and the electronic structure of BiMnO3. The calculation of the density functional theory was carried out using the generalized-gradient approximation, the Perdew–Burke–Ernzerhof parametrization and the spin polarization using the SIESTA package. We have modeled systems with a total stochiometry and small deformations caused by the oxygen and bismuth vacancies. The results indicate a significant influence of point defects on the mechanical properties (e.g. the bulk modulus) as well as on the electronic structure of the steady state of BiMnO3 crystal and they are in a good agreement with the experimental data.