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arXiv · 1302.1514

Nanostructure determination from the pair distribution function: A parametric study of the INVERT approach

Matthew J. Cliffe·Andrew L. Goodwin
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Abstract

We present a detailed study of the mechanism by which the INVERT method [Phys. Rev. Lett. 104, 125501] guides structure refinement of disordered materials. We present a number of different possible implementations of the central algorithm and explore the question of algorithm weighting. Our analysis includes quantification of the relative contributions of variance and fit-to-data terms during structure refinement, which leads us to study the roles of density fluctuations and configurational jamming in the RMC fitting process. We present a parametric study of the pair distribution function solution space for C60, a-Si and a-SiO2, which serves to highlight the difficulties faced in developing a transferable weighting scheme.

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Matthew J. Cliffe, Andrew L. Goodwin. 2013-06-12. Nanostructure determination from the pair distribution function: A parametric study of the INVERT approach. https://doi.org/10.1088/0953-8984%2F25%2F45%2F454218

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