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Živković I, Soh JR, Malanyuk O, Yadav R, Pisani F, Tehrani AM, Tolj D, Pasztorova J, Hirai D, Wei Y, Zhang W, Galdino C, Yu T, Ishii K, Demuer A, Yazyev OV, Schmitt T, Rønnow HM. Dynamic Jahn-Teller effect in the strong spin-orbit coupling regime. Nat Commun 2024; 15:8587. [PMID: 39362899 PMCID: PMC11450152 DOI: 10.1038/s41467-024-52935-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 09/20/2024] [Indexed: 10/05/2024] Open
Abstract
Exotic quantum phases, arising from a complex interplay of charge, spin, lattice and orbital degrees of freedom, are of immense interest to a wide research community. A well-known example of such an entangled behavior is the Jahn-Teller effect, where the lifting of orbital degeneracy proceeds through lattice distortions. Here we demonstrate that a highly-symmetrical 5d1 double perovskite Ba2MgReO6, comprising a 3D array of isolated ReO6 octahedra, represents a rare example of a dynamic Jahn-Teller system in the strong spin-orbit coupling regime. Thermodynamic and resonant inelastic x-ray scattering experiments, supported by quantum chemistry calculations, undoubtedly show that the Jahn-Teller instability leads to a ground-state doublet, resolving a long-standing puzzle in this family of compounds. The dynamic state of ReO6 octahedra persists down to the lowest temperatures, where a multipolar order sets in, allowing for investigations of the interplay between a dynamic JT effect and strongly correlated electron behavior.
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Affiliation(s)
- Ivica Živković
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Jian-Rui Soh
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Oleg Malanyuk
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Ravi Yadav
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Federico Pisani
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Aria M Tehrani
- Department of Materials, ETH Zurich, Zurich, Switzerland
| | - Davor Tolj
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Jana Pasztorova
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Daigorou Hirai
- Department of Applied Physics, Nagoya University, Nagoya, Japan
| | - Yuan Wei
- Paul Scherrer Institute, Villigen PSI, Switzerland
| | | | | | - Tianlun Yu
- Paul Scherrer Institute, Villigen PSI, Switzerland
| | - Kenji Ishii
- Synchrotron Radiation Research Center, National Institutes for Quantum Science and Technology, Sayo, Hyogo, Japan
| | - Albin Demuer
- Université Grenoble Alpes, INSA Toulouse, Université Toulouse Paul Sabatier, CNRS, LNCMI, Grenoble, France
| | - Oleg V Yazyev
- Chair of Computational Condensed Matter Physics, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | | | - Henrik M Rønnow
- Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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2
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Ye L, Sorensen ME, Bachmann MD, Fisher IR. Measurement of the magnetic octupole susceptibility of PrV 2Al 20. Nat Commun 2024; 15:7005. [PMID: 39143053 PMCID: PMC11325040 DOI: 10.1038/s41467-024-51269-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 08/02/2024] [Indexed: 08/16/2024] Open
Abstract
Revealing the presence of magnetic octupole order and associated octupole fluctuations in solids is a highly challenging task due to the lack of simple external fields that can couple to magnetic octupoles. Here, we demonstrate a methodology for probing the magnetic octupole susceptibility of a candidate material, PrV2Al20, using a product of magnetic field Hi and shear strain ϵjk as a composite effective field, while employing an adiabatic elastocaloric effect to probe the response. We observe Curie-Weiss behavior in the obtained octupolar susceptibility down to approximately 3 K. Although octupole order does not appear to be the leading multipolar channel in PrV2Al20, our results nevertheless reveal the presence of strong magnetic octupole fluctuations and hence demonstrate that octupole order is at least a competing state. More broadly, our results highlight how anisotropic strain can be combined with magnetic fields to probe elusive 'hidden' electronic orders.
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Affiliation(s)
- Linda Ye
- Department of Applied Physics, Stanford University, Stanford, CA, USA.
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA.
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA.
| | - Matthew E Sorensen
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA
- Department of Physics, Stanford University, Stanford, CA, USA
| | - Maja D Bachmann
- Department of Applied Physics, Stanford University, Stanford, CA, USA
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA
| | - Ian R Fisher
- Department of Applied Physics, Stanford University, Stanford, CA, USA.
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, CA, USA.
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3
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Pourovskii LV, Mosca DF, Franchini C. Ferro-octupolar Order and Low-Energy Excitations in d^{2} Double Perovskites of Osmium. PHYSICAL REVIEW LETTERS 2021; 127:237201. [PMID: 34936776 DOI: 10.1103/physrevlett.127.237201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 11/01/2021] [Indexed: 06/14/2023]
Abstract
Conflicting interpretations of experimental data preclude the understanding of the quantum magnetic state of spin-orbit coupled d^{2} double perovskites. Whether the ground state is a Janh-Teller-distorted order of quadrupoles or the hitherto elusive octupolar order remains debated. We resolve this uncertainty through direct calculations of all-rank intersite exchange interactions and inelastic neutron scattering cross section for the d^{2} double perovskite series Ba_{2}MOsO_{6} (M=Ca, Mg, Zn). Using advanced many-body first-principles methods, we show that the ground state is formed by ferro-ordered octupoles coupled by superexchange interactions within the ground-state E_{g} doublet. Computed ordering temperature of the single second-order phase transition is consistent with experimentally observed material-dependent trends. Minuscule distortions of the parent cubic structure are shown to qualitatively modify the structure of gaped magnetic excitations.
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Affiliation(s)
- Leonid V Pourovskii
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Institut Polytechnique de Paris, 91128 Palaiseau Cedex, France
- Collège de France, 11 place Marcelin Berthelot, 75005 Paris, France
| | - Dario Fiore Mosca
- Faculty of Physics and Center for Computational Materials Science, University of Vienna, Vienna 1090, Austria
| | - Cesare Franchini
- Faculty of Physics and Center for Computational Materials Science, University of Vienna, Vienna 1090, Austria
- Department of Physics and Astronomy "Augusto Righi," Alma Mater Studiorum, Università di Bologna, Bologna 40127, Italy
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4
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Yuan F, Cronkwright ZW, Lussier JA, Wiebe CR, Dube PA, Thompson CM, Munsie TJS, Luke GM, Greedan JE. The Highly Frustrated 5d 2 Double Perovskite Doppelgängers, SrLaMgReO 6 and SrLaLiOsO 6. A Comparison including Isostructural La 2LiReO 6. Inorg Chem 2021; 60:16652-16657. [PMID: 34664949 DOI: 10.1021/acs.inorgchem.1c02521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis and characterization of the double perovskite SrLaLiOsO6 is presented. It is isostructural (P21/n) and isoelectronic (5d2) with SrLaMgReO6, which has been reported previously. The cell volumes are the same to within 1.4%: i.e., these perovskites are doppelgängers. In a previous study SrLaMgReO6 showed no sign of spin order to 2 K. New data at lower temperatures disclose a maximum in the dc susceptibility near 1.5 K. As the Curie-Weiss (C-W) temperature (Θ) for this material is -161 K, an enormous frustration index, f ≈ 100, is implied (f = |Θ|/Tord). On the other hand, SrLaLiOsO6 does not follow the C-W law over the investigated susceptibility range, 2-300 K. Fitting with an added temperature independent term (TIP) gives μeff = 1.96 μB, Θ = -102 K, and TIP = 1.01 × 10-3 emu/mol. A clear zero-field-cooled (ZFC), field-cooled (FC) divergence in the dc data occurs at ∼10 K, suggesting a much reduced frustration index, f ≈ 10, relative to SrLaMgReO6. The real part of the ac susceptibility data, χ'max, shows a frequency shift that is consistent with a spin glass ground state according to the Mydosh criterion. Heat capacity data for SrLaLiOsO6 show no sign of a λ peak at 10 K and a linear dependence on temperature below 10 K, also supporting a spin glass ground state. A spin frozen ground state for SrLaMgReO6 could not be established from χ' data due to a much weaker signal. Nonetheless, the 10-fold difference in f between these doppelgänger materials is remarkable. It is possible that the enhanced covalency with the oxide ligands for Os6+ relative to Re5+ plays a major role here. Finally, a comparison with isostructural La2LiReO6 (with a much smaller f ≈ 4) is made and a correlation between the frustration level and the sense of the local distortion of the Re(Os)-O octahedron is pointed out.
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Affiliation(s)
- Fang Yuan
- Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Zachery W Cronkwright
- Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Joey A Lussier
- Department of Chemistry, University of Winnipeg, Winnipeg, R3B 2E9 Manitoba, Canada
| | - Christopher R Wiebe
- Department of Chemistry, University of Winnipeg, Winnipeg, R3B 2E9 Manitoba, Canada
| | - Paul A Dube
- Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Corey M Thompson
- Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Timothy J S Munsie
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Graeme M Luke
- Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada.,Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - John E Greedan
- Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada.,Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4L8, Canada
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Qiu WX, Zou JY, Luo AY, Cui ZH, Song ZD, Gao JH, Wang YL, Xu G. Efficient Method for Prediction of Metastable or Ground Multipolar Ordered States and Its Application in Monolayer α-RuX_{3} (X=Cl, I). PHYSICAL REVIEW LETTERS 2021; 127:147202. [PMID: 34652212 DOI: 10.1103/physrevlett.127.147202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 07/26/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
Exotic high-rank multipolar order parameters have been found to be unexpectedly active in more and more correlated materials in recent years. Such multipoles are usually dubbed "hidden orders" since they are insensitive to common experimental probes. Theoretically, it is also difficult to predict multipolar orders via ab initio calculations in real materials. Here, we present an efficient method to predict possible multipoles in materials based on linear response theory under random phase approximation. Using this method, we successfully predict two pure metastable magnetic octupolar states in monolayer α-RuCl_{3}, which is confirmed by self-consistent unrestricted Hartree-Fock calculations. We then demonstrate that these octupolar states can be stabilized in monolayer α-RuI_{3}, one of which becomes the octupolar ground state. Furthermore, we also predict a fingerprint of an orthogonal magnetization pattern produced by the octupole moment that can be easily detected by experiment. The method and the example presented in this Letter serve as a guide for searching multipolar order parameters in other correlated materials.
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Affiliation(s)
- Wen-Xuan Qiu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jin-Yu Zou
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Ai-Yun Luo
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zhi-Hai Cui
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhi-Da Song
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
| | - Jin-Hua Gao
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yi-Lin Wang
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Gang Xu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
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Thakur GS, Reuter H, Ushakov AV, Gallo G, Nuss J, Dinnebier RE, Streltsov SV, Khomskii DI, Jansen M. Na
9
Bi
5
Os
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: A Diamagnetic Oxide Featuring a Pronouncedly Jahn–Teller‐Compressed Octahedral Coordination of Osmium(VI). Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gohil S. Thakur
- Max Planck Institute for Chemical Physics of Solids Nöthnitzerstr. 40 01187 Dresden Germany
- Faculty of Chemistry and Food Chemistry Technical University 01069 Dresden Germany
| | - Hans Reuter
- Institute for Chemistry of New Materials University of Osnabrück Barbarastraße 7 49069 Osnabrück Germany
| | - Alexey V. Ushakov
- M. N. Mikheev Institute of Metal Physics Ural Branch of Russian Academy of Sciences 620041 Ekaterinburg Russia
| | - Gianpiero Gallo
- Max Planck Institute for Solid State Research Heisenbergstr. 1 70569 Stuttgart Germany
| | - Jürgen Nuss
- Max Planck Institute for Solid State Research Heisenbergstr. 1 70569 Stuttgart Germany
| | - Robert E. Dinnebier
- Max Planck Institute for Solid State Research Heisenbergstr. 1 70569 Stuttgart Germany
| | - Sergey V. Streltsov
- M. N. Mikheev Institute of Metal Physics Ural Branch of Russian Academy of Sciences 620041 Ekaterinburg Russia
- Ural Federal University 620002 Ekaterinburg Russia
| | - Daniel I. Khomskii
- II. Physikalisches Institut Universität zu Köln Zülpicher Str. 77 50937 Köln Germany
| | - Martin Jansen
- Max Planck Institute for Solid State Research Heisenbergstr. 1 70569 Stuttgart Germany
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7
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Pourovskii LV, Khmelevskyi S. Hidden order and multipolar exchange striction in a correlated f-electron system. Proc Natl Acad Sci U S A 2021; 118:e2025317118. [PMID: 33795518 PMCID: PMC8040619 DOI: 10.1073/pnas.2025317118] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The nature of order in low-temperature phases of some materials is not directly seen by experiment. Such "hidden orders" (HOs) may inspire decades of research to identify the mechanism underlying those exotic states of matter. In insulators, HO phases originate in degenerate many-electron states on localized f or d shells that may harbor high-rank multipole moments. Coupled by intersite exchange, those moments form a vast space of competing order parameters. Here, we show how the ground-state order and magnetic excitations of a prototypical HO system, neptunium dioxide NpO2, can be fully described by a low-energy Hamiltonian derived by a many-body ab initio force theorem method. Superexchange interactions between the lowest crystal-field quadruplet of Np4+ ions induce a primary noncollinear order of time-odd rank 5 (triakontadipolar) moments with a secondary quadrupole order preserving the cubic symmetry of NpO2 Our study also reveals an unconventional multipolar exchange striction mechanism behind the anomalous volume contraction of the NpO2 HO phase.
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Affiliation(s)
- Leonid V Pourovskii
- Centre de Physique Théorique, Ecole Polytechnique, CNRS, Institut Polytechnique de Paris, 91128 Palaiseau Cedex, France;
- Collège de France, 75005 Paris, France
| | - Sergii Khmelevskyi
- Research Center for Computational Materials Science and Engineering, Vienna University of Technology, 1040 Vienna, Austria
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8
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Hirai D, Hiroi Z. Possible quadrupole order in tetragonal Ba 2CdReO 6and chemical trend in the ground states of 5 d1double perovskites. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:135603. [PMID: 33429372 DOI: 10.1088/1361-648x/abda79] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
The synthesis and physical properties of the double perovskite (DP) compound Ba2CdReO6with the 5d1electronic configuration are reported. Three successive phases originating from a spin-orbit-entangledJeff= 3/2 state, confirmed by a reduced effective magnetic moment of 0.72 μB, were observed upon cooling. X-ray diffraction measurements revealed a structural transition from a high-temperature cubic structure to a low-temperature tetragonal structure atTs= 170 K, below which theJeff= 3/2 state was preserved. Magnetization, heat capacity, and thermal expansion measurements showed two more electronic transitions to a possible quadrupole ordered state atTq= 25 K and an antiferromagnetic order of dipoles with a ferromagnetic moment of ∼0.2 μBatTm= 12 K. These properties were compared with those of the DP's sister compounds Ba2BReO6(B= Mg, Zn, and Ca) and the chemical trend is discussed in terms of the mean-field theory for spin-orbit-coupled 5delectrons (2010 Chenet al Phys. Rev. B82174440). The DP Ba2BReO6compounds provide a unique opportunity for a systematic investigation of symmetry breaking in the presence of multipolar degrees of freedom.
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Affiliation(s)
- Daigorou Hirai
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Zenji Hiroi
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
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9
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Kesavan JK, Fiore Mosca D, Sanna S, Borgatti F, Schuck G, Tran PM, Woodward PM, Mitrović VF, Franchini C, Boscherini F. Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba 2Na 1-x Ca x OsO 6. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2020; 124:16577-16585. [PMID: 33643515 PMCID: PMC7901665 DOI: 10.1021/acs.jpcc.0c04807] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/08/2020] [Indexed: 05/30/2023]
Abstract
We present a combined experimental and computational study of the effect of charge doping in the osmium based double perovskite Ba2Na1-x Ca x OsO6 for 0 ≤ x ≤ 1 in order to provide a structural and electronic basis for understanding this complex Dirac-Mott insulator material. Specifically, we investigate the effects of the substitution of monovalent Na with divalent Ca, a form of charge doping or alloying that nominally tunes the system from Os7+ with a 5d1 configuration to Os6+ with 5d2 configuration. After an X-ray diffraction characterization, the local atomic and electronic structure has been experimentally probed by X-ray absorption fine structure at all the cation absorption edges at room temperature; the simulations have been performed using ab initio density functional methods. We find that the substitution of Na by Ca induces a linear volume expansion of the crystal structure which indicates an effective alloying due to the substitution process in the whole doping range. The local structure corresponds to the expected double perovskite one with rock-salt arrangement of Na/Ca in the B site and Os in the B' one for all the compositions. X-ray absorption near edge structure measurements show a smooth decrease of the oxidation state of Os from 7+ (5d1) to 6+ (5d2) with increasing Ca concentration, while the oxidation states of Ba, Na, and Ca are constant. This indicates that the substitution of Na by Ca gives rise to an effective electron transfer from the B to the B' site. The comparison between X-ray absorption measurements and ab initio simulations reveals that the expansion of the Os-O bond length induces a reduction of the crystal field splitting of unoccupied Os derived d states.
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Affiliation(s)
- Jagadesh Kopula Kesavan
- Department of Physics and Astronomy, Alma
Mater Studiorum—Università di Bologna, Bologna 40127,
Italy
| | - Dario Fiore Mosca
- Faculty of Physics, Center for Computational Materials
Science, University of Vienna, Vienna 1090,
Austria
| | - Samuele Sanna
- Department of Physics and Astronomy, Alma
Mater Studiorum—Università di Bologna, Bologna 40127,
Italy
| | - Francesco Borgatti
- Consiglio Nazionale Delle
Ricerche—Istituto per lo Studio dei Materiali Nanostrutturati
(CNR-ISMN), Bologna 40129, Italy
| | - Götz Schuck
- Helmholtz-Zentrum Berlin für
Materialien und Energie GmbH, Berlin 14109,
Germany
| | - Phuong Minh Tran
- Department of Chemistry and Biochemistry,
The Ohio State University, Columbus, Ohio 43210-1185,
United States
| | - Patrick M. Woodward
- Department of Chemistry and Biochemistry,
The Ohio State University, Columbus, Ohio 43210-1185,
United States
| | - Vesna F. Mitrović
- Department of Physics, Brown
University, Providence, Rhode Island 02912, United
States
| | - Cesare Franchini
- Department of Physics and Astronomy, Alma
Mater Studiorum—Università di Bologna, Bologna 40127,
Italy
- Faculty of Physics, Center for Computational Materials
Science, University of Vienna, Vienna 1090,
Austria
| | - Federico Boscherini
- Department of Physics and Astronomy, Alma
Mater Studiorum—Università di Bologna, Bologna 40127,
Italy
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