Fluorite-type materials in the monolayer limit

Fuente: arXiv

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Detalles Bibliográficos
Autores principales:	Ono, Shota, Pawar, Ravinder
Formato:	Preprint
Publicado:	2024
Materias:	Materials Science
Acceso en línea:	Acceder al recurso
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_version_	1866911839330238464
author	Ono, Shota Pawar, Ravinder
author_facet	Ono, Shota Pawar, Ravinder
contents	The 2H, 1T, and their distorted structures are known as prototype structures of $AB_2$ monolayers. Here, we study a puckered structure that is truncated from the (110) surface of fluorite-type materials. 53 fluorite-type materials are investigated based on first-principles approach. The formation energy calculations indicate that seven systems form the puckered structure in the monolayer limit, while other systems form either 1T, 2H, or distorted 1T structures. The puckered structures of PbF$_2$, PRh$_2$, and Ga$_2$Au exhibit negative Poisson's ratio (NPR) in the out-of-plane direction. An analytical model for the NPR is derived. The surface energy calculations predict the appearance of NPR.
format	Preprint
id	arxiv_https___arxiv_org_abs_2404_09394
institution	arXiv
publishDate	2024
record_format	arxiv
spellingShingle	Fluorite-type materials in the monolayer limit Ono, Shota Pawar, Ravinder Materials Science The 2H, 1T, and their distorted structures are known as prototype structures of $AB_2$ monolayers. Here, we study a puckered structure that is truncated from the (110) surface of fluorite-type materials. 53 fluorite-type materials are investigated based on first-principles approach. The formation energy calculations indicate that seven systems form the puckered structure in the monolayer limit, while other systems form either 1T, 2H, or distorted 1T structures. The puckered structures of PbF$_2$, PRh$_2$, and Ga$_2$Au exhibit negative Poisson's ratio (NPR) in the out-of-plane direction. An analytical model for the NPR is derived. The surface energy calculations predict the appearance of NPR.
title	Fluorite-type materials in the monolayer limit
topic	Materials Science
url	https://arxiv.org/abs/2404.09394

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