Y. Titov, N. Belyavina, M. Slobodyanik, O. Nakonechna, N. Strutynska
{"title":"Effect of strontium atoms substitution on the features of two-slab structure of Sr1-xCaxLa2Sc2O7 scandates","authors":"Y. Titov, N. Belyavina, M. Slobodyanik, O. Nakonechna, N. Strutynska","doi":"10.17721/fujcv9i1p44-50","DOIUrl":null,"url":null,"abstract":"Effects of substitution of the Strontium atoms with smaller Calcium atoms on the structural features of the Ruddlesden-Popper SrLa2Sc2O7 two-slab compound is established. The crystal structure of orthorhombic Sr0.85Ca0.15La2Sc2O7 phase with maximum degree of substitution was determined by the Rietveld method (Fmmm space group, a = 0.5766(2) nm, b = 0.5743(2) nm, c = 2.0522(7) nm). Comparison of the structural features of SrLa2Sc2O7 and Sr0.85Ca0.15La2Sc2O7 shows that such type of substitution leads to a decrease in the (La,Sr)2 - О2 interblock bond length (from 0.222 (2) nm at x = 0 to 0.215 (1) nm at x = 0.15). The decrease in interblock bond length brings the constitution of the two-dimensional structure Sr1-хCaxLa2Sc2O7 closer to the structure of the three-dimensional perovskite, leads to its instability at х > 0.15 and gives a reason to conclude that this factor causes a limitation of region of the Sr1-хCaxLa2Sc2O7 solid solutions with a slab perovskite-like structure. Presence of such structure changes is the precondition for regulation of structural-dependent features of the materials on the base of scandates alkaline-earth and rare earth metals.","PeriodicalId":42056,"journal":{"name":"French-Ukrainian Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.4000,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"French-Ukrainian Journal of Chemistry","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.17721/fujcv9i1p44-50","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Effects of substitution of the Strontium atoms with smaller Calcium atoms on the structural features of the Ruddlesden-Popper SrLa2Sc2O7 two-slab compound is established. The crystal structure of orthorhombic Sr0.85Ca0.15La2Sc2O7 phase with maximum degree of substitution was determined by the Rietveld method (Fmmm space group, a = 0.5766(2) nm, b = 0.5743(2) nm, c = 2.0522(7) nm). Comparison of the structural features of SrLa2Sc2O7 and Sr0.85Ca0.15La2Sc2O7 shows that such type of substitution leads to a decrease in the (La,Sr)2 - О2 interblock bond length (from 0.222 (2) nm at x = 0 to 0.215 (1) nm at x = 0.15). The decrease in interblock bond length brings the constitution of the two-dimensional structure Sr1-хCaxLa2Sc2O7 closer to the structure of the three-dimensional perovskite, leads to its instability at х > 0.15 and gives a reason to conclude that this factor causes a limitation of region of the Sr1-хCaxLa2Sc2O7 solid solutions with a slab perovskite-like structure. Presence of such structure changes is the precondition for regulation of structural-dependent features of the materials on the base of scandates alkaline-earth and rare earth metals.