Negative Linear Compressibility Due to Layer Sliding in a Layered Metal–Organic Framework

Abstract

Negative linear compressibility (NLC) is a rare and counterintuitive phenomenon because materials with this property would expand along one specific direction when uniformly compressed. NLC materials have a broad range of potential applications in designing pressure sensors, artificial muscles, and so on. Designing and searching for systems with NLC is desired and crucial for material and compression science. Herein, with the help of high-pressure X-ray diffraction measurements and density functional theory calculations, we find that the 2D layered Co(SCN)(pyrazine) exhibits NLC with a new mechanism: layer sliding. When compressed, the ab planes slide along the a axis, leading to the decrease of lattice parameter β, which results in the NLC effect along principal axis X (≈ -0.84a - 0.55c). The layer sliding mechanism opens exciting opportunities for seeking, designing, and synthesizing new classes of materials with anomalous mechanical properties in monoclinic layered or other related systems.

Systematic exploration of the mechanical properties of 13 621 inorganic compounds

“…This behaviour is termed negative linear compressibility (NLC), and is considered an anomalous (and rare) mechanical property 26. NLC has been quite reported in some zeolites, MOFs structures, and other framework materials 11,52–54. NLC materials have a broad range of potential applications in designing pressure sensors and artificial muscles 55,56…”

Pressure induced lattice expansion and phonon softening in layered ReS2

“…Similar expansion in the volume under hydrostatic condition was reported in the layered metal-organic framework. 41 In Fig. S4 in the supplementary material, we have shown the Rietveld refinement fit at 16.1 GPa and 25.2 GPa.…”

Anomalous Lattice Dynamics in AgC4N3: Insights From Inelastic Neutron Scattering and Density Functional Calculations

“…This type of abnormal behavior is known as negative linear or area compressibility (NLC or NAC). The behavior is basically observed in materials with highly anisotropic bonding and open framework type structures (Goodwin et al, 2008a ; Weng et al, 2008 ; Cairns et al, 2012 , 2013 ; Cairns and Goodwin, 2015 ; Wang et al, 2016 , 2017 ; Gupta et al, 2017 ; Zeng et al, 2017a , b ; Yan et al, 2018 ). The anisotropic character of elastic properties is a measure of the magnitude of NLC (or NAC) in a material.…”

“…The mechanism of the deformation of a wine rack structure produces NLC and NTE behavior in many compounds (Goodwin et al, 2008a ; David et al, 2010 ; Cairns et al, 2012 ; Zeng et al, 2017a ; Sapnik et al, 2018 ). Negative area compressibility and negative area thermal expansion are found to arise from the sliding of atomic layers as a function of pressure or temperature (Zeng et al, 2017b ).…”