First-principles study of the structural properties and magnetism of R2CoIn8 (R=Y, Pr, Nd, and Dy) intermetallic compounds
Abstract
The electronic structure of R2CoIn8 (R=Y, Pr, Nd, and Dy) intermetallic compounds is calculated from first principles based on the density functional theory (DFT). The Kohn-Sham single-particle equations of the DFT are solved using two independent computational methods, namely APW + Io and FPLO.
First the structural properties of Y2CoIn8 are studied. Good agreement of calculated equilibrium volume and c/a ratio with the experimental data is found.
Also we minimize the forces at equilibrium volume and calculate the symmetry-free structural parameters of the space group P4/mmm for Y2CoIn8. In Y2CoIn8, the Co 3d states are almost fully occupied and situated below the Fermi level.
We applied the fixed-spin-moment method and a stable paramagnetic ground state for Y2CoIn8 was found. Finally, the crystal field (CF) parameters were calculated for R=Pr, Nd and Dy from first principles.
The microscopic tetragonal CF Hamiltonian was diagonalized and the obtained eigenvalues and eigenfunctions were used to predict the anisotropy of the magnetic properties of R2CoIn8 single crystals.