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arXiv · 2602.13117

Valence-free open nanoparticle superlattices

Binay P. Nayak·Zinnia Mallick·Wenjie Wang·Prapti Kakkar·Shan Zhou·Honghu Zhang·Dmytro Nykypanchuk·Surya K. Mallapragada·Alex Travesset·David Vaknin
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Abstract

A cornerstone of advanced materials design is establishing a framework for assembling nanoparticle superstructures with tailored symmetries. A longstanding challenge has been assembling diamond-like superstructures for photonic devices. Traditionally, such open superstructures require functionalized nanoparticles with directional or anisotropic interactions, reminiscent of valence bonding in a diamond. Here, we present a robust strategy for assembling valence-free nanoparticles into a broad array of cubic superstructures. By grafting nanoparticles with oppositely charged, end-functionalized water-soluble polymers of adjustable molecular weight, we gain control over electrostatic interactions and conformational constraints. This unified approach yields lattices analogous to rock salt, CsCl, zinc-blende, diamond, and the rare simple cubic phase, with tunable lattice constants. Theoretical models and simulations elucidate the underlying interactions, providing a framework for engineering valence-free nanoparticle superlattices.

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Binay P. Nayak, Zinnia Mallick, Wenjie Wang, Prapti Kakkar, Shan Zhou, Honghu Zhang, Dmytro Nykypanchuk, Surya K. Mallapragada, Alex Travesset, David Vaknin. 2026-02-13. Valence-free open nanoparticle superlattices. https://doi.org/10.1038/s41467-026-68316-4

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