Coulomb interaction in oxygen p - shell in LDA + U method and its influence on calculated spectral and magnetic properties of transition metal oxides
نویسنده
چکیده
Coulomb interaction between electrons on p-orbitals of oxygen atom in strongly correlated compounds is not negligible, since its value (Up) has comparable order of magnitude with the value of Coulomb interaction on dorbitals of transition metal atom (Ud). We investigate the effect of taking into account Coulomb correlations in oxygen p-shell in addition to the correlations in the transition metal d-shell in frame of the LDA+U method. Our calculations for NiO, MnO and La2CuO4 show that this additional correction in general improves the agreement with experimental data for the spectral (energy gap values, relative position of the main peaks in X-ray photoemission spectroscopy (XPS) and Bremsstrahlung isohromate spectroscopy (BIS)) and magnetic properties (magnetic moment values and intersite exchange interaction parameters values). 71.27.+a Strongly correlated electron systems; heavy fermions 74.25.Jb Electronic structure 79.60.-i Photoemission and photoelectron spectra Typeset using REVTEX 1
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