Lanthanide contraction effect on crystal structures, magnetic, and dielectric properties in ordered double perovskites LnPbCoSbO{sub 6} (Ln = La, Pr, Nd)

Journal Article · Mon Apr 28 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4873457· OSTI ID:22273500

Han, L.; Yao, C. G.; Meng, J. L.; Liang, Q. S. ^[1]; Bai, Y. J. ^[2]; Meng, F. Z.; Wu, X. J.

---

1. State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)
2. Applied Chemistry Department, Chemical Engineering College, Inner Mongolia University of Technology, Huhhot 010051 (China)

The crystal structures, magnetic, and dielectric properties for the ordered double perovskites LnPbCoSbO{sub 6} (Ln = La, Pr, Nd) have been investigated. The crystal structure has been solved by Rietveld refinements of X-ray diffraction data in the monoclinic space group P2{sub 1}/n (No. 14). The Co{sup 2+} and Sb{sup 5+} ions are almost fully ordered over the B-site, and the octahedral framework displays significant tilting distortion according to the Glazer's tilt system a{sup –}a{sup –}c{sup +}. As the result of lanthanide contraction from La{sup 3+} to Nd{sup 3+}, the B-site sublattice distortions become stronger accompanying with the reduction of the tolerance factor and coordination number. The magnetization measurements show an antiferromagnetic ordering with large effective magnetic moments (μ{sub eff}) suggesting that the orbital component is significant. The maximum values of isothermal magnetization increase with the decrease in radii of rare earth ions, which is attributed to the weakening of antiferromagnetic interaction via Co{sup 2+}–O–Sb{sup 5+}–O–Co{sup 2+} paths. The dielectric constants present frequency dependence and monotonically decrease with the ionic radii reduction from La{sup 3+} to Nd{sup 3+} due to the suppression of electron transfer. These results indicate that the magnetic and dielectric properties can be tuned by controlling the degree of lattice distortion, which is realized by introducing different Ln{sup 3+} ions at the A-site.

• OSTI ID: 22273500
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 16; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANTIFERROMAGNETISM
ANTIMONY IONS
ANTIMONY OXIDES
COBALT COMPOUNDS
COBALT IONS
COORDINATION NUMBER
ELECTRON TRANSFER
FREQUENCY DEPENDENCE
LANTHANUM COMPOUNDS
LANTHANUM IONS
LEAD COMPOUNDS
MAGNETIC MOMENTS
MAGNETIZATION
MONOCLINIC LATTICES
NEODYMIUM COMPOUNDS
NEODYMIUM IONS
PERMITTIVITY
X-RAY DIFFRACTION