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Ab-initio Study of the Diffusion Coefficients in Fe-based Liquids

Published online by Cambridge University Press:  01 February 2011

Miguel Fuentes-Cabrera
Affiliation:
Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN, 37831 Department of Physics, Carnegie Mellon University, PA 15213
Don Nicholson
Affiliation:
Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN, 37831
Mike Widom
Affiliation:
Department of Physics, Carnegie Mellon University, PA 15213
Yang Wang
Affiliation:
Pittsburgh Supercomputing Center, Carnegie Mellon University, Pittsburgh, PA 15213
Marek Mihalkovic
Affiliation:
Institute of Physics, Slovak Academy of Science, Bratislava, Slovakia
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Abstract

With atomistic force fields derived from ab-initio energies and atomic forces, we cooled Fe80B20 from the liquid to the glass state. The pair-distribution functions and the diffusion coefficients were used to characterize the structural changes that Fe80B20 underwent during the simulation. In the FeFe and FeB pair-distribution functions, when the temperature is lowered the first neighbor-peak becomes narrower and the second-neighbor peak splits at around 1000K. In the BB pair-distribution we observed that the first peak undergoes a significant change at the glass transition temperature, and that the first BB peak remains present at low temperatures. That the first BB peak exists at low temperature seems to contradict the prevailing view of the structure of transition metal-metalloid glasses.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

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References

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