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arXiv · 2512.05296

Mapping vacancy and bonding electron distributions around aluminium nanovoids

Philip N. H. Nakashima·Yu-Tsun Shao·Zezhong Zhang·Andrew E. Smith·Tianyu Liu·Nikhil V. Medhekar·Joanne Etheridge·Laure Bourgeois·Jian-Min Zuo
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Abstract

All materials have defects and many contain nanostructures, both of which disrupt chemical bonding - the basis of materials properties. No experimental measurements of bonding electron distributions associated with defects and nanostructures have ever been possible. We present a method enabling such measurements and interrogate nanovoids surrounded by vacancies - the most fundamental of nanostructures and defects - in aluminium. We measure the volume of a vacancy with 3% uncertainty and map vacancy concentrations surrounding nanovoids with nanometre resolution in three dimensions where previously only two-dimensional mapping was possible. We discover that radiation-damaged voids can "heal". Our bonding measurements are depth-resolved, vacancy-sensitive, and agree with density functional theory. This work opens bonding electron density measurements to inhomogeneous nanostructured multi-phased materials so that the electronic origins of phenomena such as strengthening, weakening, interface functionality, solute diffusion and phase transformations within them may be revealed.

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Philip N. H. Nakashima, Yu-Tsun Shao, Zezhong Zhang, Andrew E. Smith, Tianyu Liu, Nikhil V. Medhekar, Joanne Etheridge, Laure Bourgeois, Jian-Min Zuo. 2025-12-04. Mapping vacancy and bonding electron distributions around aluminium nanovoids. https://arxiv.org/abs/2512.05296

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