Orbital-selective pressure-driven metal to insulator transition in FeO from dynamical mean-field theory

In this work we report the LDA+DMFT (method combining local-density approximation with dynamical mean-field theory) results of magnetic and spectral properties calculation for paramagnetic phases of FeO at ambient and high pressures (HPs). At ambient-pressure (AP) calculation gave FeO as a Mott insulator with Fe 3d shell in high-spin state. Calculated spectral functions are in a good agreement with experimental photoemission spectroscopy and IPES data. Experimentally observed metal-insulator transition at high pressure is successfully reproduced in calculations. In contrast to MnO and Fe(2)O(3) (d(5) configuration) where metal-insulator transition is accompanied by high-spin to low-spin transition, in FeO (d(6) configuration) average value of magnetic moment root )(z) is nearly the same in the insulating phase at AP and metallic phase at HP in agreement with x-ray spectroscopy data [J. Badro, V. V. Struzhkin, J. Shu, R. J. Hemley, H.-k. Mao, C.-c. Kao, J.-P. Rueff, and G. Shen, Phys. Rev. Lett. 83, 4101 (1999)]. The metal-insulator transition is orbital selective with only t(2g) orbitals demonstrating spectral function typical for strongly correlated metal (well pronounced Hubbard bands and narrow quasiparticle peak) while e(g) states remain insulating.