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arXiv · 2409.00419

Attractive and repulsive terms in multi-filament dispersion interactions

Subhojit Pal·John F. Dobson·Mathias Boström
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Abstract

Filamentary objects such as nano-wires, nanotubes and DNA are of current interest in physics, nanoscience, chemistry, biology and medicine. They can interact via strong, exceptionally long-ranged many-object van der Waals (vdW, dispersion) forces, causing them to cluster into multi-object bundles. We analyse their vdW interactions perturbatively, predicting $N$-object vdW energy contributions that alternate in sign with increasing $N$. Our findings are confirmed here via the first detailed analysis of a 4-cylinder vdW model. We also provide novel insights permitting these tendencies to be understood simply in terms of electronic screening and anti-screening. Our results suggest that a non-perturbative calculation will be required for reliable prediction of dispersion interactions in these ubiquitous systems.

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Subhojit Pal, John F. Dobson, Mathias Boström. 2024-08-31. Attractive and repulsive terms in multi-filament dispersion interactions. https://arxiv.org/abs/2409.00419

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