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arXiv · 2504.07924

A Novel Graphyne-Like Carbon Allotrope: 2D Dewar-Anthracyne

José A. S. Laranjeira·Kleuton A. L. Lima·Nicolas F. Martins·Luiz A. Ribeiro Junior·Douglas S. Galvao·Julio R. Sambrano
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Abstract

Anthracyne (2DDA). 2DDA consists of chains of Dewar-anthracenes connected by acetylenic linkages. DFT-based simulations show that 2DDA is thermally stable and exhibits no imaginary phonon modes, confirming its dynamic stability. 2DDA is metallic with Dirac-like features near the Fermi level, dominated by C pz orbitals. It shows marked mechanical anisotropy, with Young's modulus of 176.24 N/m (x) and 31.51 N/m (y), shear modulus up to 69.14 N/m, and Poisson's ratio varying from 0.27 to 0.87. The material also exhibits strong anisotropic optical absorption in the visible and ultraviolet ranges. Raman and IR spectra reveal intense bands at 648 cm-1 (Raman) and 1292 cm-1 (Infrared). Nanoribbon structures derived from 2DDA exhibit diverse electronic behaviors, from metals up to bandgap values of up to 0.42 eV, depending on the edge-type terminations and width. These findings demonstrate the 2DDA potential for nanoelectronic and optoelectronic applications.

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José A. S. Laranjeira, Kleuton A. L. Lima, Nicolas F. Martins, Luiz A. Ribeiro Junior, Douglas S. Galvao, Julio R. Sambrano. 2025-04-10. A Novel Graphyne-Like Carbon Allotrope: 2D Dewar-Anthracyne. https://arxiv.org/abs/2504.07924

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