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Title: Local structures and Raman spectra in the Ca(Zr,Ti)O3 perovskite solid solutions

Abstract

Local structures and cation distributions in perovskite Ca(Zr,Ti)O{sub 3} solid solutions were analyzed using X-ray absorption fine structure and pair-distribution functions obtained from total neutron scattering. The analyses revealed that the Zr-O and Ti-O bond distances in the solid solutions remain distinct and close to their respective values in the end-compounds, CaZrO{sub 3} and CaTiO{sub 3}. The structural strain in the solid solutions, which results from the ionic size mismatch between Zr and Ti, is accommodated by adjustment of the tilting angles for the different [BO6] octahedra. Additionally, the octahedra are distorted by bending, which affects the O-O distances while preserving a uniform distribution of the B-O distances. Combined experimental and theoretical analyses of Raman spectra demonstrated that high-frequency modes associated with the breathing of oxygen octahedra arise even in the nearly disordered solid solutions. Our results suggest a coexistence of both localized and extended Raman-active breathing vibrations, associated with the octahedra hosting the minority and majority B-cations, respectively. For the dilute solid solutions (<25 at. %), these modes yield two well-resolved Raman peaks.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
914243
Report Number(s):
BNL-78811-2007-JA
Journal ID: ISSN 0897-4756; CMATEX; TRN: US0802837
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chem. Mater.; Journal Volume: 18
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ABSORPTION; BENDING; CATIONS; DISTRIBUTION; FINE STRUCTURE; NEUTRONS; OXYGEN; PEROVSKITE; RAMAN SPECTRA; SCATTERING; SOLID SOLUTIONS; STRAINS; national synchrotron light source

Citation Formats

Levin,I., Cockayne, E., Lufaso, M., Woicik, J., and Masler, J. Local structures and Raman spectra in the Ca(Zr,Ti)O3 perovskite solid solutions. United States: N. p., 2006. Web. doi:10.1021/cm0523438.
Levin,I., Cockayne, E., Lufaso, M., Woicik, J., & Masler, J. Local structures and Raman spectra in the Ca(Zr,Ti)O3 perovskite solid solutions. United States. doi:10.1021/cm0523438.
Levin,I., Cockayne, E., Lufaso, M., Woicik, J., and Masler, J. Sun . "Local structures and Raman spectra in the Ca(Zr,Ti)O3 perovskite solid solutions". United States. doi:10.1021/cm0523438.
@article{osti_914243,
title = {Local structures and Raman spectra in the Ca(Zr,Ti)O3 perovskite solid solutions},
author = {Levin,I. and Cockayne, E. and Lufaso, M. and Woicik, J. and Masler, J.},
abstractNote = {Local structures and cation distributions in perovskite Ca(Zr,Ti)O{sub 3} solid solutions were analyzed using X-ray absorption fine structure and pair-distribution functions obtained from total neutron scattering. The analyses revealed that the Zr-O and Ti-O bond distances in the solid solutions remain distinct and close to their respective values in the end-compounds, CaZrO{sub 3} and CaTiO{sub 3}. The structural strain in the solid solutions, which results from the ionic size mismatch between Zr and Ti, is accommodated by adjustment of the tilting angles for the different [BO6] octahedra. Additionally, the octahedra are distorted by bending, which affects the O-O distances while preserving a uniform distribution of the B-O distances. Combined experimental and theoretical analyses of Raman spectra demonstrated that high-frequency modes associated with the breathing of oxygen octahedra arise even in the nearly disordered solid solutions. Our results suggest a coexistence of both localized and extended Raman-active breathing vibrations, associated with the octahedra hosting the minority and majority B-cations, respectively. For the dilute solid solutions (<25 at. %), these modes yield two well-resolved Raman peaks.},
doi = {10.1021/cm0523438},
journal = {Chem. Mater.},
number = ,
volume = 18,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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  • No abstract prepared.
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