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Title: Mn, Mg, and Zn ilmenite group titanates: A reconnaissance rietveld study

Abstract

Ecandrewsite-geikielite (Zn{sub 1/2}Mg{sub 1/2}TiO{sub 3}), ecandrewsite-pyrophanite (Zn{sub 1/2}Mn{sub 1/2}TiO{sub 3}), pyrophanite-geikielite (Mg{sub 1/2}Mn{sub 1/2}TiO{sub 3}), and ecandrewsite-pyrophanite-geikielite (Zn{sub 1/3}Mn{sub 1/3}Mg{sub 1/3}TiO{sub 3}) titanates were synthesized at 900-1000 deg. C at ambient pressure. All of the compounds adopt R- ilmenite-type structures. These structures were refined by the Rietveld method from X-ray powder diffraction data. Unit cell parameters and unit cell volumes decrease with decreasing average radii of the A{sup 2+} cation. All structures consist of distorted AO{sub 6} and TiO{sub 6} octahedra. In common with pyrophanite and ilmenite, the distortion of the AO{sub 6} octahedra is less than that of the TiO{sub 6} octahedra. Data are given for the volumes and distortion indexes of all coordination polyhedra.

Authors:
 [1];  [2]
  1. Russian Academy of Sciences, Geological Institute, Kola Science Center (Russian Federation)
  2. Lakehead University, Department of Geology (Canada), E-mail: rmitchel@lakeheadu.ca
Publication Date:
OSTI Identifier:
21091487
Resource Type:
Journal Article
Resource Relation:
Journal Name: Crystallography Reports; Journal Volume: 51; Journal Issue: 3; Other Information: DOI: 10.1134/S1063774506030047; Copyright (c) 2006 Nauka/Interperiodica; Article Copyright (c) 2006 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ILMENITE; MAGNESIUM COMPOUNDS; MANGANESE COMPOUNDS; TITANATES; X-RAY DIFFRACTION; ZINC COMPOUNDS

Citation Formats

Liferovich, R. P., and Mitchell, R. H.. Mn, Mg, and Zn ilmenite group titanates: A reconnaissance rietveld study. United States: N. p., 2006. Web. doi:10.1134/S1063774506030047.
Liferovich, R. P., & Mitchell, R. H.. Mn, Mg, and Zn ilmenite group titanates: A reconnaissance rietveld study. United States. doi:10.1134/S1063774506030047.
Liferovich, R. P., and Mitchell, R. H.. Mon . "Mn, Mg, and Zn ilmenite group titanates: A reconnaissance rietveld study". United States. doi:10.1134/S1063774506030047.
@article{osti_21091487,
title = {Mn, Mg, and Zn ilmenite group titanates: A reconnaissance rietveld study},
author = {Liferovich, R. P. and Mitchell, R. H.},
abstractNote = {Ecandrewsite-geikielite (Zn{sub 1/2}Mg{sub 1/2}TiO{sub 3}), ecandrewsite-pyrophanite (Zn{sub 1/2}Mn{sub 1/2}TiO{sub 3}), pyrophanite-geikielite (Mg{sub 1/2}Mn{sub 1/2}TiO{sub 3}), and ecandrewsite-pyrophanite-geikielite (Zn{sub 1/3}Mn{sub 1/3}Mg{sub 1/3}TiO{sub 3}) titanates were synthesized at 900-1000 deg. C at ambient pressure. All of the compounds adopt R- ilmenite-type structures. These structures were refined by the Rietveld method from X-ray powder diffraction data. Unit cell parameters and unit cell volumes decrease with decreasing average radii of the A{sup 2+} cation. All structures consist of distorted AO{sub 6} and TiO{sub 6} octahedra. In common with pyrophanite and ilmenite, the distortion of the AO{sub 6} octahedra is less than that of the TiO{sub 6} octahedra. Data are given for the volumes and distortion indexes of all coordination polyhedra.},
doi = {10.1134/S1063774506030047},
journal = {Crystallography Reports},
number = 3,
volume = 51,
place = {United States},
year = {Mon May 15 00:00:00 EDT 2006},
month = {Mon May 15 00:00:00 EDT 2006}
}
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