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Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6)

[Image: see text] We present a combined experimental and computational study of the effect of charge doping in the osmium based double perovskite Ba(2)Na(1–x)Ca(x)OsO(6) for 0 ≤ x ≤ 1 in order to provide a structural and electronic basis for understanding this complex Dirac–Mott insulator material....

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Autores principales: Kesavan, Jagadesh Kopula, Fiore Mosca, Dario, Sanna, Samuele, Borgatti, Francesco, Schuck, Götz, Tran, Phuong Minh, Woodward, Patrick M., Mitrović, Vesna F., Franchini, Cesare, Boscherini, Federico
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2020
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7901665/
https://www.ncbi.nlm.nih.gov/pubmed/33643515
http://dx.doi.org/10.1021/acs.jpcc.0c04807
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author Kesavan, Jagadesh Kopula
Fiore Mosca, Dario
Sanna, Samuele
Borgatti, Francesco
Schuck, Götz
Tran, Phuong Minh
Woodward, Patrick M.
Mitrović, Vesna F.
Franchini, Cesare
Boscherini, Federico
author_facet Kesavan, Jagadesh Kopula
Fiore Mosca, Dario
Sanna, Samuele
Borgatti, Francesco
Schuck, Götz
Tran, Phuong Minh
Woodward, Patrick M.
Mitrović, Vesna F.
Franchini, Cesare
Boscherini, Federico
author_sort Kesavan, Jagadesh Kopula
collection PubMed
description [Image: see text] We present a combined experimental and computational study of the effect of charge doping in the osmium based double perovskite Ba(2)Na(1–x)Ca(x)OsO(6) 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 Os(7+) with a 5d(1) configuration to Os(6+) with 5d(2) 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+ (5d(1)) to 6+ (5d(2)) 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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spelling pubmed-79016652021-02-24 Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6) Kesavan, Jagadesh Kopula Fiore Mosca, Dario Sanna, Samuele Borgatti, Francesco Schuck, Götz Tran, Phuong Minh Woodward, Patrick M. Mitrović, Vesna F. Franchini, Cesare Boscherini, Federico J Phys Chem C Nanomater Interfaces [Image: see text] We present a combined experimental and computational study of the effect of charge doping in the osmium based double perovskite Ba(2)Na(1–x)Ca(x)OsO(6) 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 Os(7+) with a 5d(1) configuration to Os(6+) with 5d(2) 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+ (5d(1)) to 6+ (5d(2)) 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. American Chemical Society 2020-07-08 2020-07-30 /pmc/articles/PMC7901665/ /pubmed/33643515 http://dx.doi.org/10.1021/acs.jpcc.0c04807 Text en Made available through a Creative Commons CC-BY License (http://pubs.acs.org/page/policy/authorchoice_ccby_termsofuse.html)
spellingShingle Kesavan, Jagadesh Kopula
Fiore Mosca, Dario
Sanna, Samuele
Borgatti, Francesco
Schuck, Götz
Tran, Phuong Minh
Woodward, Patrick M.
Mitrović, Vesna F.
Franchini, Cesare
Boscherini, Federico
Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6)
title Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6)
title_full Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6)
title_fullStr Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6)
title_full_unstemmed Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6)
title_short Doping Evolution of the Local Electronic and Structural Properties of the Double Perovskite Ba(2)Na(1–x)Ca(x)OsO(6)
title_sort doping evolution of the local electronic and structural properties of the double perovskite ba(2)na(1–x)ca(x)oso(6)
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7901665/
https://www.ncbi.nlm.nih.gov/pubmed/33643515
http://dx.doi.org/10.1021/acs.jpcc.0c04807
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