Instability of the rhodium magnetic moment as origin of the metamagnetic phase transition in alpha-FeRh

Based on ab initio total energy calculations we show that two magnetic states of rhodium atoms together with competing ferromagnetic and antiferromagnetic exchange interactions are responsible for a temperature induced metamagnetic phase transition, which experimentally is observed for stoichiometric alpha-FeRh. A first-principle spin-based model allows to reproduce this first-order metamagnetic transition by means of Monte Carlo simulations. Further inclusion of spacial variation of exchange parameters leads to a realistic description of the experimental magneto-volume effects in alpha-FeRh.Comment: 10 pages, 13 figures, accepted for publication in Phys. Rev.

Magnetostriction of terbium molybdate in high magnetic field

75.80.+q Magnetomechanical and magnetoelectric effects, magnetostriction, 05.70.-a Thermodynamics,

Electronic and optical properties of β-Tb2(MoO4)3: DFT+U approach

Vlastnosti bazálního stavu β-Tb2 (MoO4) 3 jsou zkoumány za použití funkční hustoty teorie plus U-Hubbard Hamiltonian. Pro zjištění vlivu spin-polarizace na vlastnosti půdního stavu ortorombického β-Tb2 (MoO4) 3 jsme provedli výpočty spin-polarizace a spin-polarizovanou elektronickou strukturu pásma pro spin-up (↑) a spin-down (↓)The ground state properties of β-Tb2(MoO4)3 are investigated using the density functional theory plus U-Hubbard Hamiltonian. To ascertain the influence of the spin-polarization on the ground state properties of orthorhombic β-Tb2(MoO4)3, we have performed spin-polarization calculations and the spin-polarized electronic band structure for spin-up (↑) and spin-down (↓) are calculate