High-temperature crystal structure and transport properties of the layered cuprates Ln{sub 2}CuO{sub 4}, Ln=Pr, Nd and Sm

Journal Article · Tue Mar 15 00:00:00 EDT 2011 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.01.035· OSTI ID:21494232

Kaluzhskikh, M S; Kazakov, S M; Mazo, G N ^[1]; Antipov, E V ^[1]; Gippius, A A ^[2]; Fedotov, Yu; Bredikhin, S I ^[3]; Liu, Yi; Svensson, G; Shen, Z ^[4]

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1. Department of Chemistry, Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation)
2. Department of Physics, Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation)
3. Institute of Solid State Physics RAS, 142432 Chernogolovka, Moscow Region (Russian Federation)
4. Department of Materials and Environmental Chemistry, Stockholm University, S-10691 Stockholm (Sweden)

High-temperature crystal structure of the layered cuprates Ln{sub 2}CuO{sub 4}, Ln=Pr, Nd and Sm with tetragonal T'-structure was refined using X-ray powder diffraction data. Substantial anisotropy of the thermal expansion behavior was observed in their crystal structures with thermal expansion coefficients (TEC) along a- and c-axis changing from TEC(a)/TEC(c){approx}1.37 (Pr) to 0.89 (Nd) and 0.72 (Sm). Temperature dependence of the interatomic distances in Ln{sub 2}CuO{sub 4} shows significantly lower expansion rate of the chemical bond between Pr and oxygen atoms (O1) belonging to CuO{sub 2}-planes (TEC(Pr-O1)=11.7 ppm K{sup -1}) in comparison with other cuprates: TEC (Nd-O1)=15.2 ppm K{sup -1} and TEC (Sm-O1)=15.1 ppm K{sup -1}. High-temperature electrical conductivity of Pr{sub 2}CuO{sub 4} is the highest one in the whole studied temperature range (298-1173 K): 0.1-108 S/cm for Pr{sub 2}CuO{sub 4}, 0.07-23 S/cm for Nd{sub 2}CuO{sub 4} and 2x10{sup -4}-9 S/cm for Sm{sub 2}CuO{sub 4}. The trace diffusion coefficient (D{sub T}) of oxygen for Pr{sub 2}CuO{sub 4} determined by isotopic exchange depth profile (IEDP) technique using secondary ion mass spectrometry (SIMS) varies in the range 7.2x10{sup -13} cm{sup 2}/s (973 K) and 3.8x10{sup -10} cm{sup 2}/s (1173 K) which are in between those observed for the manganese and cobalt-based perovskites. -- Graphical abstract: Anomaly anisotropic thermal expansion behavior was observed for Pr{sub 2}CuO{sub 4} in comparison with Ln{sub 2}CuO{sub 4}, Ln=Pr and Nd having tetragonal T'-structure with thermal expansion coefficients (TEC) along a- and c-axis changing from TEC(a)/TEC(c){approx}1.37 (Pr) to 0.89 (Nd) and 0.72 (Sm). It was found that the trace diffusion coefficient (D{sub T}) of oxygen in Pr{sub 2}CuO{sub 4} determined by secondary ion mass spectrometry (SIMS) varies in the range 7.2x10{sup -13} cm{sup 2}/s (973 K) and 3.8x10{sup -10} cm{sup 2}/s (1173 K) which are in between those observed for the manganese and cobalt-based perovskites. Display Omitted Research highlights: {yields} Anisotropic high-temperature thermal expansion behavior of T'-Ln{sub 2}CuO{sub 4}, Ln=Pr, Nd and Sm. {yields} Anomalous expansion behavior of Pr{sub 2}CuO{sub 4} in comparison with Ln{sub 2}CuO{sub 4}, Ln=Nd and Sm. {yields} High-temperature electrical conductivity of Pr{sub 2}CuO{sub 4} is higher in comparison with other T'-Ln{sub 2}CuO{sub 4}. {yields} Values of the oxygen trace diffusion coefficient for Pr{sub 2}CuO{sub 4} are between those reported for the Mn- and Co-based perovskites.

• OSTI ID: 21494232
• Journal Information: Journal of Solid State Chemistry, Vol. 184, Issue 3; Other Information: DOI: 10.1016/j.jssc.2011.01.035; PII: S0022-4596(11)00046-6; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ANISOTROPY
CHEMICAL BONDS
COPPER OXIDES
CRYSTAL STRUCTURE
CUPRATES
DIFFUSION
ELECTRIC CONDUCTIVITY
INTERATOMIC DISTANCES
ION MICROPROBE ANALYSIS
ISOTOPIC EXCHANGE
MASS SPECTROSCOPY
NEODYMIUM COMPOUNDS
PEROVSKITES
PRASEODYMIUM COMPOUNDS
SAMARIUM COMPOUNDS
TEMPERATURE DEPENDENCE
THERMAL EXPANSION
X-RAY DIFFRACTION
CHALCOGENIDES
CHEMICAL ANALYSIS
COHERENT SCATTERING
COPPER COMPOUNDS
DIFFRACTION
DISTANCE
ELECTRICAL PROPERTIES
EXPANSION
MICROANALYSIS
MINERALS
NONDESTRUCTIVE ANALYSIS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SCATTERING
SPECTROSCOPY
TRANSITION ELEMENT COMPOUNDS