Parallel-Self-Assembling Stack, Center-Capture Effect, and Reactivity-Enhancing Effect of N-Layer (<i>N</i> = 1, 2, 3) Cyclo[18]carbon.

Abstract

Cyclo[18]carbon (C₁₈) is an captivating allotrope of carbon synthesized recently, which has drawn the attention among scientists. There are still few studies on the dynamic behaviors of C₁₈. To gain knowledge in this area, we systematically explored the stacking behaviors and the oxidation kinetics of C₁₈, as well the electronic transport behaviors of C₁₈ oxides, by density functional theory and nonequilibrium Green's function calculations combined with reactive force field molecular dynamics simulations. The parallel-self-assembling behaviors were observed in the stack of two- or three-layer C₁₈. During the oxidation process of C₁₈, we found an evident center-capture effect in which the hollow rings would preferentially attract an O₂ molecule into their centers. Moreover, the adsorption of O₂ on the O₂-doped rings was dramatically enhanced by the O₂ at the center of the ring, showing the reactivity-enhancing effect. The excellent electron transport property of central-O₂-doped C₁₈ among 13 types of C₁₈ oxides demonstrates the potential of C₁₈ oxides as promising molecular devices for various applications. This study reveals the dynamic behaviors of C₁₈ and provides theoretical guidance for use of C₁₈ and C₁₈ oxides in molecular devices.