{"title":"Robust Unusually High Valence Fe5+ State and Large Magnetic Interaction Change in the Double Perovskites La2–xCaxLiFeO6–0.5x","authors":"Masato Goto, Kazunori Sato, Wei-tin Chen, Wei-Hsiang Huang, Yuichi Shimakawa","doi":"10.1021/acs.chemmater.4c03494","DOIUrl":null,"url":null,"abstract":"We successfully synthesized Ca-substituted <i>B</i>-site-ordered double perovskites La<sub>2–<i>x</i></sub>Ca<i><sub><i>x</i></sub></i>LiFeO<sub>6</sub> by using high-pressure techniques and investigated site-substitution effects on the stability of unusually high valence Fe ions and their magnetic properties. Our research revealed the robust Fe<sup>5+</sup> state against the aliovalent substitution at the <i>A</i> site, as seen in the actual composition La<sub>2–<i>x</i></sub>Ca<i><sub><i>x</i></sub></i>LiFeO<sub>6–0.5<i>x</i></sub>. Introducing oxygen vacancies is a key factor in this discovery, as it significantly weakens the strong antiferromagnetic interaction for <i>x</i> = 0, transforming it into a weak ferromagnetic one for <i>x</i> > 0.3. This significant interaction change, coupled with the partial randomness of the magnetic interactions, easily releases the geometrical spin frustration of Fe<sup>5+</sup> located on a face-centered-cubic lattice with just 5% Ca substitution. These results deepen our understanding of the site-substitution effects in geometrically frustrated <i>B</i>-site-ordered double perovskites.","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"31 1","pages":""},"PeriodicalIF":7.2000,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemistry of Materials","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1021/acs.chemmater.4c03494","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
We successfully synthesized Ca-substituted B-site-ordered double perovskites La2–xCaxLiFeO6 by using high-pressure techniques and investigated site-substitution effects on the stability of unusually high valence Fe ions and their magnetic properties. Our research revealed the robust Fe5+ state against the aliovalent substitution at the A site, as seen in the actual composition La2–xCaxLiFeO6–0.5x. Introducing oxygen vacancies is a key factor in this discovery, as it significantly weakens the strong antiferromagnetic interaction for x = 0, transforming it into a weak ferromagnetic one for x > 0.3. This significant interaction change, coupled with the partial randomness of the magnetic interactions, easily releases the geometrical spin frustration of Fe5+ located on a face-centered-cubic lattice with just 5% Ca substitution. These results deepen our understanding of the site-substitution effects in geometrically frustrated B-site-ordered double perovskites.
期刊介绍:
The journal Chemistry of Materials focuses on publishing original research at the intersection of materials science and chemistry. The studies published in the journal involve chemistry as a prominent component and explore topics such as the design, synthesis, characterization, processing, understanding, and application of functional or potentially functional materials. The journal covers various areas of interest, including inorganic and organic solid-state chemistry, nanomaterials, biomaterials, thin films and polymers, and composite/hybrid materials. The journal particularly seeks papers that highlight the creation or development of innovative materials with novel optical, electrical, magnetic, catalytic, or mechanical properties. It is essential that manuscripts on these topics have a primary focus on the chemistry of materials and represent a significant advancement compared to prior research. Before external reviews are sought, submitted manuscripts undergo a review process by a minimum of two editors to ensure their appropriateness for the journal and the presence of sufficient evidence of a significant advance that will be of broad interest to the materials chemistry community.