Theoretical analysis of [5.7](n)cyclacenes: closed-shell cyclacene isomers

The [5.7](n)cyclacenes represent a novel class of all sp(2)-hybridized carbon structures. In contrast to the isomeric [n]cyclacenes, [5.7](n)cyclacenes are predicted at the B3LYP/6-31G* level of theory to have stable, closed-shell singlet ground state configurations. Predicted geometries, electronic structures, band gaps, nucleus-independent chemical shift (NICS) values, and strain energies for this new family of cyclic conjugated molecules are presented.