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arXiv · 1507.02606

Competing Hydrostatic Compression Mechanisms in Nickel Cyanide

Jasper Adamson·Timothy C. Lucas·Andrew B. Cairns·Nicholas P. Funnell·Matthew G. Tucker·Annette K. Kleppe·Joseph A. Hriljac·Andrew L. Goodwin
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Abstract

We use variable-pressure neutron and X-ray diffraction measurements to determine the uniaxial and bulk compressibilities of nickel(II) cyanide, Ni(CN)$_2$. Whereas other layered molecular framework materials are known to exhibit negative area compressibility, we find that Ni(CN)$_2$ does not. We attribute this difference to the existence of low-energy in-plane tilt modes that provide a pressure-activated mechanism for layer contraction. The experimental bulk modulus we measure is about four times lower than that reported elsewhere on the basis of density functional theory methods [{\it Phys. Rev. B} {\bf 83}, 024301 (2011)].

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Jasper Adamson, Timothy C. Lucas, Andrew B. Cairns, Nicholas P. Funnell, Matthew G. Tucker, Annette K. Kleppe, Joseph A. Hriljac, Andrew L. Goodwin. 2015-07-09. Competing Hydrostatic Compression Mechanisms in Nickel Cyanide. https://doi.org/10.1016/j.physb.2015.09.027

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