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arXiv · 2508.07971

Extreme anharmonicity and thermal contraction of 1D wires

Chiara Cignarella·Lorenzo Bastonero·Lorenzo Monacelli·Nicola Marzari
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Abstract

Ultrathin nanowires could play a central role in next-generation downscaled electronics. Here, we explore some of the most promising candidates identified from previous high-throughput screening: CuC$_2$, TaSe$_3$, and AuSe$_2$, to gain insight into the thermodynamic and anharmonic behaviors of nanowires that could be exfoliated from weakly-bonded three-dimensional materials. We analyze thermal stability, linear thermal expansion, and anharmonic heat capacity using the stochastic self-consistent harmonic approximation. Notably, our work unveils exotic features common among all the 1D wires: a colossal record negative thermal expansion and very large deviations from the Dulong-Petit law due to strong anharmonicity.

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Chiara Cignarella, Lorenzo Bastonero, Lorenzo Monacelli, Nicola Marzari. 2025-08-11. Extreme anharmonicity and thermal contraction of 1D wires. https://doi.org/10.1021/acs.nanolett.5c04282

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