Pseudogap Value in the Energy Spectrum of LaOFeAs: a Fixed Spin Moment Treatment

The experimental data available to date in the literature corresponding to the paramagnetic-spin density wave transition in nonsuperconducting LaOFeAs are discussed. In particular, we note that a relative decrease in the density of states on the Fermi level and formation of a pseudogap occur upon a spin density wave transition. The values of these quantities are not properly described in density functional theory. The agreement with experimental estimations becomes more accurate with the use of a fixed spin moment procedure when the iron spin moment is set to m experimental value. Strong electron correlations that are not included m the present calculation scheme may lead both to a decrease in the spin moment and to a renormalization of the energy spectrum in the vicinity of the Fermi level for correct description of the discussed characteristics.