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The Si Vacancy: An Example of a Pressure-Sensitive Jahn-Teller System

Published online by Cambridge University Press:  01 January 1992

Eugen Tarnow
Eugen Tarnow*
Affiliation:
Los Alamos National Laboratory, MS D429, Los Alamos, NM 87545;
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Abstract

We calculate the trends in the Jahn-Teller (JT) parameters of the Si vacancy as a function of the breathing mode coordinate. Using ab-initio local-density-functional theory and Hellman--Feynman forces we find the couplings between the JT modes and the breathing mode to be significant. Since the breathing mode coordinate is very sensitive to pressure we predict a pressure-sensitive JT contribution to the effective electronic correlation energy U. Furthermore we find that the tetragonal JT energy increasingly dominates over the trigonal energy as the breathing coordinate decreases due to a softening of the tetragonal spring constant.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 291: Symposium O – Materials Theory and Modeling , 1992 , 67
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

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