{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T08:40:01Z","timestamp":1759135201242,"version":"3.44.0"},"reference-count":30,"publisher":"IOP Publishing","issue":"39","license":[{"start":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T00:00:00Z","timestamp":1759104000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/iop-standard\/v1"},{"start":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T00:00:00Z","timestamp":1759104000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"DOI":"10.13039\/501100004359","name":"Swedish Research Council","doi-asserted-by":"crossref","award":["2022-06725"],"award-info":[{"award-number":["2022-06725"]}],"id":[{"id":"10.13039\/501100004359","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100007595","name":"Belarusian Republican Foundation for Fundamental Research","doi-asserted-by":"crossref","award":["F23RNF-159"],"award-info":[{"award-number":["F23RNF-159"]}],"id":[{"id":"10.13039\/100007595","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["J. Phys.: Condens. Matter"],"published-print":{"date-parts":[[2025,9,29]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>The results of <jats:italic>ab initio<\/jats:italic> calculations performed for Sr<jats:sub>2<\/jats:sub>IrO<jats:sub>4<\/jats:sub> using the density functional theory with the spin-orbit coupling and the onsite Hubbard-U correction applied to the Ir\u2212d states are reported in order to provide more insights into known experimental data. The results demonstrate that in the stoichiometric oxide all Ir ions are in the +4 oxidation state. In the presence of an O vacancy some Ir ions turn into +3 and +2 states that is contrary to experimental observations where only the +3 state has been observed. These transitions are accompanied by the change in the magnetic moments from 0.10 <jats:italic>\u03bc<\/jats:italic>\n                  <jats:sub>B<\/jats:sub> for Ir<jats:sup>4+<\/jats:sup> to 0.26 <jats:italic>\u03bc<\/jats:italic>\n                  <jats:sub>B<\/jats:sub> and 0.31 <jats:italic>\u03bc<\/jats:italic>\n                  <jats:sub>B<\/jats:sub> for Ir<jats:sup>3+<\/jats:sup> and Ir<jats:sup>2+<\/jats:sup>, respectively. Depending on the site where the O vacancy is formed, the change in the oxidation state leads to either the appearance of empty defect states in the gap or filled localized Ir d-states. The reasons for the absence of the Ir<jats:sup>2+<\/jats:sup> state in experimental data are also discussed. The formation of a Sr vacancy does not cause alternation in ion oxidation states providing instead a remarkable change in the band structure of the oxide resulting in the appearance of Dirac cones at the Fermi level. No experimentally determined Ir<jats:sup>5+<\/jats:sup> state could be detected in the presence of an Ir vacancy or an additional interstitial oxygen indicating a more complex nature of defects to provide the +5 state.<\/jats:p>","DOI":"10.1088\/1361-648x\/ae0914","type":"journal-article","created":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T08:14:24Z","timestamp":1759133664000},"page":"395502","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["The origin of different iridium oxidation states of Sr<sub>2<\/sub>IrO<sub>4<\/sub>"],"prefix":"10.1088","volume":"37","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3004-7996","authenticated-orcid":true,"given":"Dmitri B","family":"Migas","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrew B","family":"Filonov","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexander L","family":"Daniluyk","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-5605-7686","authenticated-orcid":true,"given":"Natalia V","family":"Skorodumova","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"266","published-online":{"date-parts":[[2025,9,29]]},"reference":[{"key":"cmae0914bib1","doi-asserted-by":"publisher","DOI":"10.1002\/adma.201904508","type":"journal-article","article-title":"The Jeff = 1\/2 antiferromagnet Sr2IrO4: a golden avenue toward new physics and functions","volume":"32","author":"Lu","year":"2020","journal-title":"Adv. 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All rights, including for text and data mining, AI training, and similar technologies, are reserved.","name":"copyright_information","label":"Copyright Information"},{"value":"2025-06-24","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2025-09-18","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2025-09-29","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}