Figure 1

Optimized structures of the ground states (GSs/GSs′) and transition states (TSs) of (a) C₁₀H₁₀, (b) C₈H₈, (c) C₉H₁₀, and (d) C₈BH₉, with the lowest vibrational frequencies ν_min and relative energies ΔE_a indicated at PBE0 and CCSD(T) levels, respectively. Typical calculated C-C bond lengths are indicated in Å.