2003/06/08 by I. A. Nekrasov, S. V. Streltsov, M. A. Korotin +2 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Multiferroics and related materials #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.68.235113
published as Phys. Rev. B 68, 235113 (2003) · 13 pages, 6 figures
arxiv created 2003/06/08 · openalex publication_date 2003/12/24 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/29
We present first-principles (local-density approximation) LDA+U calculations of electronic structure and magnetic state for LaCoO3 and HoCoO3. Low-spin to intermediate-spin state transition was found in our calculations using experimental crystallographic data for both materials with a much higher transition temperature for HoCoO3, which agrees well with the experimental estimations. Low-spin state t2g6eg0 (nonmagnetic) to intermediate-spin state t2g5eg1 (magnetic) transition of Co3+ ions happens due to the competition between crystal-field t2g\ensuremath-eg splitting and effective exchange interaction between 3d spin orbitals. We show that the difference in crystal structure parameters for HoCoO3 and LaCoO3 due to the smaller ionic radius of Ho ion comparing with La ion results in stronger crystal-field splitting for HoCoO3 (0.09eV\ensuremath≈1000K larger than for LaCoO3) and hence tips the balance between the low-spin and intermediate-spin states to the nonmagnetic solution in HoCoO3.