The oxygen deficient Ruddlesden-Popper La{sub 3}Ni{sub 2}O{sub 7-{delta}} ({delta} = 0.65) phase: Structure and properties
- Department of Chemistry and Chemical Biology, Rutgers, State University of New Jersey, 610 Taylor Road, Piscataway, NJ 08854 (United States)
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States)
La{sub 3}Ni{sub 2}O{sub 7-{delta}} ({delta} = 0.65) was synthesized by hydrogen reduction of the parent La{sub 3}Ni{sub 2}O{sub 7} Ruddlesden-Popper nickelate. The crystal structure of La{sub 3}Ni{sub 2}O{sub 6.35} (space group: I4/mmm, a = 3.8742 (1) A and c = 20.055 (1) A) has been determined from powder neutron diffraction data by the Rietveld method for the first time. The oxygen vacancies are located in the LaO {sub x} planes between two of the NiO{sub 2} layers. Removal of these oxygen atoms from the parent phase results in a significant ({approx}0.4 A) shrinkage of the perovskite block along c-direction and splitting of the Ni position. The major part of Ni cations is surrounded by five oxygen atoms forming square pyramids, while the rest are coordinated to six octahedrally arranged oxygen atoms. Over the 170-400 K temperature range, the conductivity of La{sub 3}Ni{sub 2}O{sub 6.35} follows Mott's variable range hopping model modified for a 2D case.
- OSTI ID:
- 20895214
- Journal Information:
- Materials Research Bulletin, Vol. 41, Issue 5; Other Information: DOI: 10.1016/j.materresbull.2006.01.028; PII: S0025-5408(06)00053-5; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
- Country of Publication:
- United States
- Language:
- English
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