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arXiv · 2212.01704

Boron nanotube structure explored by evolutionary computations

Tomasz Tarkowski·Nevill Gonzalez Szwacki
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Abstract

In this work, we explore the structure of single-wall boron nanotubes with large diameters (about 21~Å) and a broad range of surface densities of atoms. The computations are done using an evolutionary approach combined with a nearest neighbors model Hamiltonian. For the most stable nanotubes, the number of 5-coordinated boron atoms is about $63\%$ of the total number of atoms forming the nanotubes, whereas about $11\%$ are boron vacancies. For hole densities smaller than about 0.22, the boron nanotubes exhibit randomly distributed hexagonal holes and are more stable than a flat stripe structure and a quasi-flat B$_{36}$ cluster. For larger hole densities ($> 0.22$) the boron nanotubes resemble porous tubular structures with hole sizes that depend on the surface densities of boron atoms.

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Tomasz Tarkowski, Nevill Gonzalez Szwacki. 2022-12-03. Boron nanotube structure explored by evolutionary computations. https://arxiv.org/abs/2212.01704

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