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arXiv · 2303.07637

Mechanical properties of 2D metal-organic and covalent-organic frameworks with non trivial topological band dispersion

Abstract

Using density functional theory (DFT), we investigate mechanical properties of a few 2D metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs) having Dirac and flat bands. These porous materials have become a subject of great captivation because of their physical stability, distinctive structural characteristics and large surface to volume ratio. The inherent porosity of these frameworks gives rise to many fascinating and occasionally surprising phenomena, which makes them potential candidates for technological applications. For reliable usage of MOFs/COFs in functional nanodevice and practical application, it is quite imperative to investigate their mechanical properties. Thus, herein a particular attention is paid to study elastic deformation of few 2D MOFs and COFs having non trivial topological band dispersion in the regime with linear dependency of stress upon strain. Specially, we consider different types of deformation and find all the components of elastic tensor from the stress-strain and energy-strain curves. These findings may provide useful information to fabricate the MOFs/COFs based devices by lowering the number of experiments.

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Priyadarshini Kapri, Takuto Kawakami, Mikito Koshino. 2023-03-14. Mechanical properties of 2D metal-organic and covalent-organic frameworks with non trivial topological band dispersion. https://arxiv.org/abs/2303.07637

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