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Title: Structure, Magnetism and Conductivity in Epitaxial Ti-doped -Fe2O3 Hematite: Experiment and density functional theory calculations.

Abstract

We explore the feasibility of growing epitaxial Ti-doped -Fe2O3 in which Ti(IV) substitutes for Fe(III) preferentially in one magnetic sublattice, but not the other. Such a structure has been predicted by first-principles theory to be energetically likely, and is expected to yield interesting and useful magnetic and electronic properties. However, we find that a majority of Ti dopants disperse and occupy random cation sites in both magnetic sublattices. Density functional theory predicts that the magnetically ordered and magnetically random structures are nearly isoenergetic.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
908939
Report Number(s):
PNNL-SA-48675
Journal ID: ISSN 0163-1829; PRBMDO; 13492; TRN: US200722%%822
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review, B: Condensed Matter; Journal Volume: 75; Journal Issue: 10
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; HEMATITE; MAGNETISM; EPITAXY; TITANIUM; DOPED MATERIALS; DENSITY FUNCTIONAL METHOD; MOLECULAR STRUCTURE; Environmental Molecular Sciences Laboratory

Citation Formats

Droubay, Timothy C., Rosso, Kevin M., Heald, Steve M., Mccready, David E., Wang, Chong M., and Chambers, Scott A.. Structure, Magnetism and Conductivity in Epitaxial Ti-doped -Fe2O3 Hematite: Experiment and density functional theory calculations.. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.75.104412.
Droubay, Timothy C., Rosso, Kevin M., Heald, Steve M., Mccready, David E., Wang, Chong M., & Chambers, Scott A.. Structure, Magnetism and Conductivity in Epitaxial Ti-doped -Fe2O3 Hematite: Experiment and density functional theory calculations.. United States. doi:10.1103/PhysRevB.75.104412.
Droubay, Timothy C., Rosso, Kevin M., Heald, Steve M., Mccready, David E., Wang, Chong M., and Chambers, Scott A.. Fri . "Structure, Magnetism and Conductivity in Epitaxial Ti-doped -Fe2O3 Hematite: Experiment and density functional theory calculations.". United States. doi:10.1103/PhysRevB.75.104412.
@article{osti_908939,
title = {Structure, Magnetism and Conductivity in Epitaxial Ti-doped -Fe2O3 Hematite: Experiment and density functional theory calculations.},
author = {Droubay, Timothy C. and Rosso, Kevin M. and Heald, Steve M. and Mccready, David E. and Wang, Chong M. and Chambers, Scott A.},
abstractNote = {We explore the feasibility of growing epitaxial Ti-doped -Fe2O3 in which Ti(IV) substitutes for Fe(III) preferentially in one magnetic sublattice, but not the other. Such a structure has been predicted by first-principles theory to be energetically likely, and is expected to yield interesting and useful magnetic and electronic properties. However, we find that a majority of Ti dopants disperse and occupy random cation sites in both magnetic sublattices. Density functional theory predicts that the magnetically ordered and magnetically random structures are nearly isoenergetic.},
doi = {10.1103/PhysRevB.75.104412},
journal = {Physical Review, B: Condensed Matter},
number = 10,
volume = 75,
place = {United States},
year = {Fri Mar 16 00:00:00 EDT 2007},
month = {Fri Mar 16 00:00:00 EDT 2007}
}
  • We explore the feasibility of growing epitaxial Ti-doped {alpha}-Fe{sub 2}O{sub 3} hematite in which Ti(IV) substitutes for Fe(III) preferentially in one magnetic sublattice but not the other. Such a structure has been predicted by first-principles theory to be energetically favorable, and is expected to yield interesting and useful magnetic and electronic properties. However, we find experimentally that a majority of Ti dopants disperse and occupy random cation sites in both magnetic sublattices. Density functional theory predicts that the magnetically ordered and magnetically random structures are nearly isoenergetic.
  • We explore the feasibility of growing epitaxial Ti-doped {alpha}-Fe{sub 2}O{sub 3} hematite in which Ti(IV) substitutes for Fe(III) preferentially in one magnetic sublattice but not the other. Such a structure has been predicted by first-principles theory to be energetically favorable, and is expected to yield interesting and useful magnetic and electronic properties. However, we find experimentally that a majority of Ti dopants disperse and occupy random cation sites in both magnetic sublattices. Density functional theory predicts that the magnetically ordered and magnetically random structures are nearly isoenergetic.
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