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Title: Structure and properties of α-NaFeO{sub 2}-type ternary sodium iridates

Abstract

The synthesis, structure, and elementary magnetic and electronic properties are reported for layered compounds of the type Na{sub 3−x}MIr{sub 2}O{sub 6} and Na{sub 3−x}M{sub 2}IrO{sub 6}, where M is a transition metal from the 3d series (M=Zn, Cu, Ni, Co, Fe and Mn). The rhombohedral structures, in space group R−3m, were determined by refinement of neutron and synchrotron powder diffraction data. No clear evidence for long range 2:1 or 1:2 honeycomb-like M/Ir ordering was found in the neutron powder diffraction patterns except in the case of M=Zn, and thus in general the compounds are best designated as sodium deficient α-NaFeO{sub 2}-type phases with formulas Na{sub 1−x}M{sub 1/3}Ir{sub 2/3}O{sub 2} or Na{sub 1−x}M{sub 2/3}Ir{sub 1/3}O{sub 2}. Synchrotron powder diffraction patterns indicate that several of the compounds likely have honeycomb in-plane metal–iridium ordering with disordered stacking of the layers. All the compounds are sodium deficient under our synthetic conditions and are black and insulating. Weiss constants derived from magnetic susceptibility measurements indicate that Na{sub 0.62}Mn{sub 0.61}Ir{sub 0.39}O{sub 2}, Na{sub 0.80}Fe{sub 2/3}Ir{sub 1/3}O{sub 2}, Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2}, and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2} display dominant antiferromagnetic interactions. For Na{sub 0.90}Co{sub 1/3}Ir{sub 2/3}O{sub 2} the dominant magneticmore » interactions at low temperature are ferromagnetic while at high temperatures they are antiferromagnetic; there is also a change in the effective moment. Low temperature specific heat measurements (to 2 K) on Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2} indicate the presence of a broad magnetic ordering transition. X-ray absorption spectroscopy shows that iridium is at or close to the 4+ oxidation state in all compounds. {sup 23}Na nuclear magnetic resonance measurements comparing Na{sub 2}IrO{sub 3} to Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2} and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2} provide strong indications that the electron spins are short-range ordered in the latter two materials. Na{sub 0.62}Mn{sub 0.61}Ir{sub 0.39}O{sub 2}, Na{sub 0.80}Fe{sub 2/3}Ir{sub 1/3}O{sub 2}, Na{sub 0.90}Co{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2} and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2} are spin glasses. (CSD-numbers: Na{sub 0.62}Mn{sub 0.61}Ir{sub 0.39}O{sub 2}: 426657, Na{sub 0.80}Fe{sub 2/3}Ir{sub 1/3}O{sub 2}: 426659, Na{sub 0.90}Co{sub 1/3}Ir{sub 2/3}O{sub 2}: 426658, Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}: 426656, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2}: 426655, and Na{sub 2.8}ZnIr{sub 2}O{sub 6}: 426660.) - Graphical abstract: Diffraction patterns of Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2} and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2}: neutron diffraction patterns in the main panel and synchrotron diffraction in the insets. The patterns show a small amount of ordering in the transition metal iridium layer. Display Omitted - Highlights: • We report six ternary sodium iridates with the α-NaFeO{sub 2} structure. • Compounds Na{sub 1−x}M{sub 1/3}Ir{sub 2/3}O{sub 2}, M=Co, Ni, Cu, Zn and Na{sub 1−x}M{sub 2/3}Ir{sub 1/3}O{sub 2}, M=Mn, Fe. • Rietveld refinement of powder neutron diffraction data. • All compounds are spin glasses. • NMR comparison to Na{sub 2}IrO{sub 3}.« less

Authors:
 [1];  [1];  [2];  [2];  [1];  [3]; ;  [3];  [3];  [1]; ; ;  [4]; ;  [5]; ;  [4];  [1]
  1. Department of Chemistry, Princeton University, Princeton, NJ 08544 (United States)
  2. NIST Center for Neutron Research, Gaithersburg, MD 20899-6102 (United States)
  3. Leibniz Institute for Solid State and Materials Research IFW, Dresden (Germany)
  4. Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden (Germany)
  5. National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan, ROC (China)
Publication Date:
OSTI Identifier:
22274215
Resource Type:
Journal Article
Journal Name:
Journal of Solid State Chemistry
Additional Journal Information:
Journal Volume: 210; Journal Issue: 1; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0022-4596
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION SPECTROSCOPY; ANTIFERROMAGNETISM; INTERACTIONS; IRIDIUM; MAGNETIC SUSCEPTIBILITY; MAGNETIZATION; NEUTRON DIFFRACTION; NEUTRONS; NUCLEAR MAGNETIC RESONANCE; POWDERS; SODIUM; SPACE GROUPS; SPECIFIC HEAT; SPIN GLASS STATE; SYNCHROTRONS; SYNTHESIS; TRIGONAL LATTICES; X-RAY SPECTROSCOPY

Citation Formats

Baroudi, Kristen, Yim, Cindi, Wu, Hui, Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742-2115, Huang, Qingzhen, Roudebush, John H., Vavilova, Eugenia, Zavoisky Physical Technical Institute, Russian Academy of Sciences, Kazan, Grafe, Hans-Joachim, Kataev, Vladislav, Buechner, Bernd, Institut für Festkörperphysik, Technische Universität Dresden, Dresden, Ji, Huiwen, Kuo, Changyang, Hu, Zhiwei, Pi, Tun-Wen, Pao, Chiwen, Lee, Jyhfu, Mikhailova, Daria, Hao Tjeng, Liu, and Cava, R. J. Structure and properties of α-NaFeO{sub 2}-type ternary sodium iridates. United States: N. p., 2014. Web. doi:10.1016/J.JSSC.2013.11.017.
Baroudi, Kristen, Yim, Cindi, Wu, Hui, Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742-2115, Huang, Qingzhen, Roudebush, John H., Vavilova, Eugenia, Zavoisky Physical Technical Institute, Russian Academy of Sciences, Kazan, Grafe, Hans-Joachim, Kataev, Vladislav, Buechner, Bernd, Institut für Festkörperphysik, Technische Universität Dresden, Dresden, Ji, Huiwen, Kuo, Changyang, Hu, Zhiwei, Pi, Tun-Wen, Pao, Chiwen, Lee, Jyhfu, Mikhailova, Daria, Hao Tjeng, Liu, & Cava, R. J. Structure and properties of α-NaFeO{sub 2}-type ternary sodium iridates. United States. doi:10.1016/J.JSSC.2013.11.017.
Baroudi, Kristen, Yim, Cindi, Wu, Hui, Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742-2115, Huang, Qingzhen, Roudebush, John H., Vavilova, Eugenia, Zavoisky Physical Technical Institute, Russian Academy of Sciences, Kazan, Grafe, Hans-Joachim, Kataev, Vladislav, Buechner, Bernd, Institut für Festkörperphysik, Technische Universität Dresden, Dresden, Ji, Huiwen, Kuo, Changyang, Hu, Zhiwei, Pi, Tun-Wen, Pao, Chiwen, Lee, Jyhfu, Mikhailova, Daria, Hao Tjeng, Liu, and Cava, R. J. Sat . "Structure and properties of α-NaFeO{sub 2}-type ternary sodium iridates". United States. doi:10.1016/J.JSSC.2013.11.017.
@article{osti_22274215,
title = {Structure and properties of α-NaFeO{sub 2}-type ternary sodium iridates},
author = {Baroudi, Kristen and Yim, Cindi and Wu, Hui and Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742-2115 and Huang, Qingzhen and Roudebush, John H. and Vavilova, Eugenia and Zavoisky Physical Technical Institute, Russian Academy of Sciences, Kazan and Grafe, Hans-Joachim and Kataev, Vladislav and Buechner, Bernd and Institut für Festkörperphysik, Technische Universität Dresden, Dresden and Ji, Huiwen and Kuo, Changyang and Hu, Zhiwei and Pi, Tun-Wen and Pao, Chiwen and Lee, Jyhfu and Mikhailova, Daria and Hao Tjeng, Liu and Cava, R. J.},
abstractNote = {The synthesis, structure, and elementary magnetic and electronic properties are reported for layered compounds of the type Na{sub 3−x}MIr{sub 2}O{sub 6} and Na{sub 3−x}M{sub 2}IrO{sub 6}, where M is a transition metal from the 3d series (M=Zn, Cu, Ni, Co, Fe and Mn). The rhombohedral structures, in space group R−3m, were determined by refinement of neutron and synchrotron powder diffraction data. No clear evidence for long range 2:1 or 1:2 honeycomb-like M/Ir ordering was found in the neutron powder diffraction patterns except in the case of M=Zn, and thus in general the compounds are best designated as sodium deficient α-NaFeO{sub 2}-type phases with formulas Na{sub 1−x}M{sub 1/3}Ir{sub 2/3}O{sub 2} or Na{sub 1−x}M{sub 2/3}Ir{sub 1/3}O{sub 2}. Synchrotron powder diffraction patterns indicate that several of the compounds likely have honeycomb in-plane metal–iridium ordering with disordered stacking of the layers. All the compounds are sodium deficient under our synthetic conditions and are black and insulating. Weiss constants derived from magnetic susceptibility measurements indicate that Na{sub 0.62}Mn{sub 0.61}Ir{sub 0.39}O{sub 2}, Na{sub 0.80}Fe{sub 2/3}Ir{sub 1/3}O{sub 2}, Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2}, and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2} display dominant antiferromagnetic interactions. For Na{sub 0.90}Co{sub 1/3}Ir{sub 2/3}O{sub 2} the dominant magnetic interactions at low temperature are ferromagnetic while at high temperatures they are antiferromagnetic; there is also a change in the effective moment. Low temperature specific heat measurements (to 2 K) on Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2} indicate the presence of a broad magnetic ordering transition. X-ray absorption spectroscopy shows that iridium is at or close to the 4+ oxidation state in all compounds. {sup 23}Na nuclear magnetic resonance measurements comparing Na{sub 2}IrO{sub 3} to Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2} and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2} provide strong indications that the electron spins are short-range ordered in the latter two materials. Na{sub 0.62}Mn{sub 0.61}Ir{sub 0.39}O{sub 2}, Na{sub 0.80}Fe{sub 2/3}Ir{sub 1/3}O{sub 2}, Na{sub 0.90}Co{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2} and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2} are spin glasses. (CSD-numbers: Na{sub 0.62}Mn{sub 0.61}Ir{sub 0.39}O{sub 2}: 426657, Na{sub 0.80}Fe{sub 2/3}Ir{sub 1/3}O{sub 2}: 426659, Na{sub 0.90}Co{sub 1/3}Ir{sub 2/3}O{sub 2}: 426658, Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}: 426656, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2}: 426655, and Na{sub 2.8}ZnIr{sub 2}O{sub 6}: 426660.) - Graphical abstract: Diffraction patterns of Na{sub 0.92}Ni{sub 1/3}Ir{sub 2/3}O{sub 2}, Na{sub 0.86}Cu{sub 1/3}Ir{sub 2/3}O{sub 2} and Na{sub 0.89}Zn{sub 1/3}Ir{sub 2/3}O{sub 2}: neutron diffraction patterns in the main panel and synchrotron diffraction in the insets. The patterns show a small amount of ordering in the transition metal iridium layer. Display Omitted - Highlights: • We report six ternary sodium iridates with the α-NaFeO{sub 2} structure. • Compounds Na{sub 1−x}M{sub 1/3}Ir{sub 2/3}O{sub 2}, M=Co, Ni, Cu, Zn and Na{sub 1−x}M{sub 2/3}Ir{sub 1/3}O{sub 2}, M=Mn, Fe. • Rietveld refinement of powder neutron diffraction data. • All compounds are spin glasses. • NMR comparison to Na{sub 2}IrO{sub 3}.},
doi = {10.1016/J.JSSC.2013.11.017},
journal = {Journal of Solid State Chemistry},
issn = {0022-4596},
number = 1,
volume = 210,
place = {United States},
year = {2014},
month = {2}
}