title: KFeCuTe2: a new compound to study the removal of interstitial Fe in layered tellurides.
abstract: A single crystal of a new layered telluride KFeCuTe2has been successfully synthesized by the self-flux method, which is formed by intercalating K in the parent telluride Fe1+xCuTe2. This new compound crystallizes in the space group I4/mmm with the interstitial Fe in pristine Fe1+xCuTe2completely removed after K intercalation. X-ray photoelectron spectroscopy (XPS) shows that after intercalation, the valence of Fe switched from a mixture of +2 and +3 to the single trivalent one. The KFeCuTe2is a Mott semiconductor (Eg= 1.06 eV) with a larger resistivity than that of Fe1+xCuTe2due to the absence of electron doping from interstitial Fe atoms. Most importantly, the magnetic susceptibility shows the antiferromagnetic transition in KFeCuTe2at 60 K, instead of the spin-glass behavior in Fe1+xCuTe2, indicating the crucial role of interstitial Fe in breaking the long-range magnetic ordering. Our work provides a new compound to study the effect of interstitial Fe on the crystal and magnetic structure in layered tellurides.
authors.affiliation: Department of Chemistry, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China. wxyuanwz@163.com.
authors.forename: Fan
authors.initials: F
authors.lastname: Sun
authors.affiliation: Department of Chemistry, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China. wxyuanwz@163.com.
authors.forename: Zhongnan
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Research & Development Center for Functional Crystals, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Physical Chemistry, State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Lin
authors.affiliation: Research & Development Center for Functional Crystals, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Da
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department of Chemistry, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China. wxyuanwz@163.com.
authors.forename: Wenxia
authors.identifier: http://orcid.org/0000-0002-3521-3538
authors.initials: W
authors.lastname: Yuan