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arXiv · 1710.11589

The influence of defects on the thermal conductivity of compressed LiF

Reese E. Jones·Donald K. Ward
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Abstract

Defect formation in LiF, which is used as an observation window in ramp and shock experi- ments, has significant effects on its transmission properties. Given the extreme conditions of the experiments it is hard to measure the change in transmission directly. Using molecular dynam- ics, we estimate the change in conductivity as a function of the concentration of likely point and extended defects using a Green-Kubo technique with careful treatment of size-effects. With this data, we form a model of the mean behavior and its estimated error; then, we use this model to predict the conductivity of a large sample of defective LiF resulting from a direct simulation of ramp compression as a demonstration of the accuracy of its predictions. Given estimates of defect densities in a LiF window used in an experiment, the model can be used to correct the observations of thermal energy through the window. In addition, the methodology we develop is extensible to modelling, with quantified uncertainty, the effects of a variety of defects on thermal conductivity of solid materials.

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Reese E. Jones, Donald K. Ward. 2017-10-31. The influence of defects on the thermal conductivity of compressed LiF. https://doi.org/10.1103/physrevb.97.054103

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