Ground-state magnetic structure of hexagonal YMnO3 compound: A non-collinear spin density functional theory study

With objective to determine ground state magnetic structure of multiferroic hexagonal YMnO3 we performed systematic non-collinear spin density-functional-theory (DFT) study of six possible magnetic configurations of Mn ions, treating exchange and correlation effects by standard local-spin-density approximation (LSDA), by LSDA including Hubbard correction (LSDA+U), and taking into account the spin orbit interaction. We found that P6(3) and P6'(3) configurations are the most stable ones, with very small energy difference between them. This result substantiates conclusions of latest neutron-diffraction studies. Both configurations are characterized by canting of Mn spins that produces weak ferro-(P6(3)) or anti-ferromagnetism (P6'(3)) along the hexagonal c-axis. The calculated Mn magnetic moments are found to be in good agreement with experiment, and electronic structure generally agrees with previous non-collinear spin DFT studies that used different basis sets and exchange and correlation functionals. (C) 2016 Elsevier B.V. All rights reserved.