119784 20230519145524.0 doi 10.1103/PhysRevB.103.094445 sideral 126654 ART-2021-126654 eng Kazak N.V. Spin state crossover in Co3BO5 2021 Access copy available to the general public Unrestricted We have investigated the spin and oxidation states of Co in Co3BO5 using x-ray magnetic circular dichroism (XMCD) and dc magnetic susceptibility measurements. At low temperatures, XMCD experiments have been performed at the Co K-edge in Co3BO5 and Co2FeBO5 single crystals in the fully ferrimagnetically ordered phase. The Co (K-edge) XMCD signal is found to be related to the Co2+ magnetic sublattices in both compounds, providing strong experimental support for the low-spin (LS) Co3+ scenario. The paramagnetic susceptibility is highly anisotropic. An estimation of the effective magnetic moment in the temperature range 100-250 K correlates well with two Co2+ ions in the high-spin (HS) state and some orbital contribution, while Co3+ remains in the LS state. The crystal structure of the Co3BO5 single crystal has been solved in detail at the T range 296-703 K. The unit cell parameters and volume show anomalies at 500 and 700 K. The octahedral environment of the Co4 site strongly changes with heating. The generalized gradient approximation with Hubbard U correction calculations have revealed that, at low-temperatures, the system is insulating with a band gap of 1.4 eV, and the Co2+ ions are in the HS state, while Co3+ are in the LS state. At high temperatures (T > 700 K), the charge ordering disappears, and the system becomes metallic with all Co ions in 3d7 electronic configuration and HS state. © 2021 American Physical Society. info:eu-repo/grantAgreement/ES/DGA/E12-20R info:eu-repo/grantAgreement/ES/MINECO/MAT2017-83468-R info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 3.908 2021 MATERIALS SCIENCE, MULTIDISCIPLINARY 163 / 345 = 0.472 2021 Q2 T2 PHYSICS, CONDENSED MATTER 23 / 69 = 0.333 2021 Q2 T2 PHYSICS, APPLIED 52 / 161 = 0.323 2021 Q2 T1 1.537 2021 Condensed Matter Physics 2021 Q1 Electronic, Optical and Magnetic Materials 2021 Q1 6.9 2021 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion Platunov M.S. Knyazev Y.V. Molokeev M.S. Gorev M.V. Ovchinnikov S.G. Pchelkina Z.V. Gapontsev V.V. Streltsov S.V. Bartolomé J. Universidad de Zaragoza (orcid)0000-0002-6517-1236 Arauzo A. Universidad de Zaragoza (orcid)0000-0002-5999-341X Yumashev V.V. Gavrilkin S.Y. Wilhelm F. Rogalev A. 0 X Universidad de Zaragoza Serv.Gral. Apoyo Investigación Servicios. Div.Caract.Físi.Quí 2003 395 Universidad de Zaragoza Dpto. Física Materia Condensa. Área Física Materia Condensada 103, 9 (2021), 094445 [19 pp] Phys. Rev. B Physical Review B 2469-9950 1599626 http://zaguan.unizar.es/record/119784/files/texto_completo.pdf Postprint 2356547 http://zaguan.unizar.es/record/119784/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:119784 articulos driver 2023-05-18-15:25:10 ARTICLE