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arXiv · 1112.2528

Positive-Definiteness of the Blended Force-Based Quasicontinuum Method

Xingjie Helen Li·Mitchell Luskin·Christoph Ortner
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Abstract

The development of consistent and stable quasicontinuum models for multi-dimensional crystalline solids remains a challenge. For example, proving stability of the force-based quasicontinuum (QCF) model remains an open problem. In 1D and 2D, we show that by blending atomistic and Cauchy--Born continuum forces (instead of a sharp transition as in the QCF method) one obtains positive-definite blended force-based quasicontinuum (B-QCF) models. We establish sharp conditions on the required blending width.

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Xingjie Helen Li, Mitchell Luskin, Christoph Ortner. 2011-12-12. Positive-Definiteness of the Blended Force-Based Quasicontinuum Method. https://arxiv.org/abs/1112.2528

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