{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"volume":["116(4)"],"submitter":["Wang CH"],"pubmed_abstract":["The exact superconducting phase of K<sub>2-<i>x</i></sub> Fe<sub>4+<i>y</i></sub> Se<sub>5</sub> has so far not been conclusively decided since its discovery due to its intrinsic multiphase in early material. In an attempt to resolve this mystery, we have carried out systematic structural studies on a set of well-controlled samples with exact chemical stoichiometry K<sub>2-<i>x</i></sub> Fe<sub>4+<i>x</i></sub> Se<sub>5</sub> (<i>x</i> = 0-0.3) that are heat-treated at different temperatures. Using high-resolution synchrotron radiation X-ray diffraction, our investigations have determined the superconducting transition by focusing on the detailed temperature evolution of the crystalline phases. Our results show that superconductivity appears only in those samples that have been treated at "],"journal":["Proceedings of the National Academy of Sciences of the United States of America"],"pagination":["1104-1109"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC6347709"],"repository":["biostudies-literature"],"pubmed_title":["Role of the extra Fe in K<sub>2-<i>x</i></sub> Fe<sub>4+<i>y</i></sub> Se<sub>5</sub> superconductors."],"pmcid":["PMC6347709"],"pubmed_authors":["Yang JY","Huang GT","Wang CH","Sheu HS","Lee CC","Lee JJ","Wang MJ","Wu MK"],"additional_accession":[]},"is_claimable":false,"name":"Role of the extra Fe in K<sub>2-<i>x</i></sub> Fe<sub>4+<i>y</i></sub> Se<sub>5</sub> superconductors.","description":"The exact superconducting phase of K<sub>2-<i>x</i></sub> Fe<sub>4+<i>y</i></sub> Se<sub>5</sub> has so far not been conclusively decided since its discovery due to its intrinsic multiphase in early material. In an attempt to resolve this mystery, we have carried out systematic structural studies on a set of well-controlled samples with exact chemical stoichiometry K<sub>2-<i>x</i></sub> Fe<sub>4+<i>x</i></sub> Se<sub>5</sub> (<i>x</i> = 0-0.3) that are heat-treated at different temperatures. Using high-resolution synchrotron radiation X-ray diffraction, our investigations have determined the superconducting transition by focusing on the detailed temperature evolution of the crystalline phases. Our results show that superconductivity appears only in those samples that have been treated at ","dates":{"release":"2019-01-01T00:00:00Z","publication":"2019 Jan","modification":"2025-05-29T22:28:11.363Z","creation":"2025-05-29T22:28:11.363Z"},"accession":"S-EPMC6347709","cross_references":{"pubmed":["30617078"],"doi":["10.1073/pnas.1815237116"]}}