Fig. 1. (a) Structure of an armchair carbon nanotube (CNT) and its relation to [n]cycloparaphenylenes; (b) HOMO (left) and excited state (right) S_1′ orbitals of [12]CPP and (c) HOMO (left) and excited state (right) S_1′ orbitals of [5]CPP. Orbitals have been calculated using CAM-B3LYP/STO-3G level of theory. (d) meta[n]CPPs with broken symmetry in this work.