Theoretical insight into the doubly antiaromatic carbon allotrope cyclo[16]carbon

Abstract

A new carbon allotrope, cyclo[16]carbon (C₁₆), has recently been successfully synthesized. It is hypothesized to exhibit double antiaromatic properties owing to the 4n π electrons. Theoretical calculations are a feasible method for systematically studying the structures and properties of unstable antiaromatic molecules. The results show that C₁₆ has a planar structure characterized by alternating long and short bonds with D_8h, and a strong antiaromatic characteristic originates from the two perpendicular π systems. We performed an extensive comparative analysis of C₁₆ and the aromatic cyclo[18]carbon, C₁₈. This study offers valuable insight into the structural and electronic characteristics of C₁₆ and could inspire innovative applications and avenues for its utilization in various fields.