DFT study of the polarization behaviors of various distorted barium titanate crystals: The role of atomic displacements

摘要: Abstract A Local Density Approximation (LDA) was employed to investigate the influence of applied strains on valence charge distributions, atomic displacements, Ti O (3) bond distances and total polarizations in barium titanate (BaTiO3). Four types various were imposed perfect tetragonal BaTiO3 along a, c, ab abc axial directions. Electromechanical properties evaluated LDA framework a good agreement with previous results achieved. The show that, cases strains, values polarization are almost constant negative increased by gradual increasing positive after sudden enhancement at about +0.1% strain. In case c-strain, oxygen atoms underwent highest displacements linearly abc-strain, represent both features. abc-strain similar behavior like c-strain region, is same as a- ab-strain cases. abc-strains −0.3% +0.1%, an abrupt jump curve small change, observed due abnormal displacements. most direct relation between distance also beheld. Finally, effects distributions studied. It found that there Valence Charge Asymmetry 3d -orbitals.