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arXiv · 2410.21623

Giant Negative Linear Compressibility in Orthorhombic Copper Cyanide

Swayam Kesari·Alka B. Garg·Nilesh P. Salke·Rekha Rao
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Abstract

Most reported negative linear compressibility (NLC) materials exhibit either a small NLC over a large pressure range or a high NLC over a very small pressure range. Here, we report the remarkable discovery of giant NLC in the low-temperature form of CuCN (LT-CuCN) over an unusually large pressure range. High-pressure XRD studies on LT-CuCN observed the NLC of -20.5 TPa-1 along the a-axis at zero pressure, and the ambient orthorhombic phase remained stable up to 9.8 GPa. Pressure and temperature-dependent Raman studies identified the phonon vibrations responsible for NLC and negative thermal expansion (NTE).

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Swayam Kesari, Alka B. Garg, Nilesh P. Salke, Rekha Rao. 2024-10-29. Giant Negative Linear Compressibility in Orthorhombic Copper Cyanide. https://arxiv.org/abs/2410.21623

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