Rodrigues Hugo X, Armando Hudson R, da Silva Daniel A, da Costa João Paulo J, Ribeiro Luiz A, Pereira Marcelo L
Institute of Physics, University of Brasília, 70910-900 Brasília-DF, Brazil.
Computational Materials Laboratory, University of Brasília, 70910-900 Brasília-DF, Brazil.
J Chem Theory Comput. 2025 Mar 11;21(5):2612-2625. doi: 10.1021/acs.jctc.4c01578. Epub 2025 Jan 28.
Two-dimensional (2D) nanomaterials are at the forefront of potential technological advancements. Carbon-based materials have been extensively studied since synthesizing graphene, which revealed properties of great interest for novel applications across diverse scientific and technological domains. New carbon allotropes continue to be explored theoretically, with several successful synthesis processes for carbon-based materials recently achieved. In this context, this study investigates the mechanical and thermal properties of DHQ-based monolayers and nanotubes, a carbon allotrope characterized by 4-, 6-, and 10-membered carbon rings, with a potential synthesis route using naphthalene as a molecular precursor. A machine-learned interatomic potential (MLIP) was developed to explore this nanomaterial's mechanical and thermal behavior at larger scales than those accessible through the first-principles calculations. The MLIP was trained on data derived from the DFT/PBE (density functional theory/Perdew-Burke-Ernzerhof) level using ab initio molecular dynamics (AIMD). Classical molecular dynamics (CMD) simulations, employing the trained MLIP, revealed that Young's modulus of DHQ-based nanotubes ranges from 127 to 243 N/m, depending on chirality and diameter, with fracture occurring at strains between 13.6 and 17.4% of the initial length. Regarding thermal response, a critical temperature of 2200 K was identified, marking the onset of a transition to an amorphous phase at higher temperatures.
二维（2D）纳米材料处于潜在技术进步的前沿。自从合成石墨烯以来，碳基材料就受到了广泛研究，石墨烯展现出的特性在不同科学和技术领域的新型应用中极具吸引力。新的碳同素异形体仍在理论上不断探索，最近已成功实现了几种碳基材料的合成方法。在此背景下，本研究调查了以萘为分子前驱体的潜在合成路线制备的、由4元、6元和10元碳环构成的碳同素异形体——基于DHQ的单层和纳米管的力学和热学性质。开发了一种机器学习原子间势（MLIP），以探索这种纳米材料在比第一性原理计算所能达到的更大尺度上的力学和热学行为。该MLIP使用从头算分子动力学（AIMD）在从DFT/PBE（密度泛函理论/佩德韦-伯克-恩泽霍夫）水平导出的数据上进行训练。采用经过训练的MLIP进行的经典分子动力学（CMD）模拟表明，基于DHQ的纳米管的杨氏模量范围为127至243 N/m，具体取决于手性和直径，在初始长度的13.6%至17.4%的应变下发生断裂。关于热响应，确定了2200 K的临界温度，这标志着在更高温度下向非晶相转变的开始。
