Preparation, XRD and Raman spectroscopic studies on new compounds RE {sub 2}Hf{sub 2}O{sub 7} (RE=Dy, Ho, Er, Tm, Lu, Y): Pyrochlores or defect-fluorite?
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)
A series of compositions with the general formula RE {sub 2}Hf{sub 2}O{sub 7} (RE=Dy, Ho, Er, Tm, Y and Lu) was prepared by a standard solid-state route and characterized by powder X-ray diffraction (XRD) and Raman spectroscopy. As per theoretical modeling reported in literature, some of these materials were predicted to exist in pyrochlore lattice. However, a careful X-ray diffraction, Raman spectroscopic and synchrotron radiation-XRD study revealed that under the experimental conditions used in the present investigation, out of all the RE {sub 2}Hf{sub 2}O{sub 7} samples only Dy{sub 2}Hf{sub 2}O{sub 7} has got a tendency to form a pyrochlore structure. All the other (Ho, Er, Tm, Lu, Y) hafnates crystallize in a defect-fluorite structure. In order to further ascertain these inferences, a few more RE {sub 2}Hf{sub 2}O{sub 7} samples (La, Nd, Sm) i.e., with larger RE{sup 3+} ions were also prepared and the results were compared. - Graphical abstract: Display Omitted.
- OSTI ID:
- 20905340
- Journal Information:
- Journal of Solid State Chemistry, Vol. 179, Issue 7; Other Information: DOI: 10.1016/j.jssc.2006.03.036; PII: S0022-4596(06)00184-8; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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