Physics – Condensed Matter – Materials Science
Scientific paper
2002-12-23
Physics
Condensed Matter
Materials Science
14 pages including 10 figures. To Physical Review B. Replaced after corrections due to referees' remarks
Scientific paper
10.1103/PhysRevB.68.014120
K$_{1-x}$Li$_{x}$TaO$_3$ (KLT) solid solutions exhibit a variety of interesting physical phenomena related to large displacements of Li-ions from ideal perovskite A-site positions. First-principles calculations for KLT supercells were used to investigate these phenomena. Lattice dynamics calculations for KLT exhibit a Li off-centering instability. The energetics of Li-displacements for isolated Li-ions and for Li-Li pairs up to 4th neighbors were calculated. Interactions between nearest neighbor Li-ions, in a Li-Li pair, strongly favor ferroelectric alignment along the pair axis. Such Li-Li pairs can be considered "seeds" for polar nanoclusters in KLT. Electrostriction, local oxygen relaxation, coupling to the KT soft-mode, and interactions with neighboring Li-ions all enhance the polarization from Li off-centering. Calculated hopping barriers for isolated Li-ions and for nearest neighbor Li-Li pairs are in good agreement with Arrhenius fits to experimental dielectric data.
Burton Benjamin P.
Cockayne Eric
Prosandeev S. A.
No associations
LandOfFree
The Energetics of Li Off-Centering in K$_{1-x}$Li$_x$TaO$_3$; First Principles Calculations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Energetics of Li Off-Centering in K$_{1-x}$Li$_x$TaO$_3$; First Principles Calculations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Energetics of Li Off-Centering in K$_{1-x}$Li$_x$TaO$_3$; First Principles Calculations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-74384