Gas-Phase Heat of Formation Values for Buckminsterfullerene (C60), C70 Fullerene (C70), Corannulene, Coronene, Sumanene, and Other Polycyclic Aromatic Hydrocarbons Calculated Using Density Functional Theory (M06 2X) Coupled with a Versatile Inexpensive Group-Equivalent Approach
journal contributionposted on 02.08.2018, 17:40 by John A. Bumpus
A straightforward procedure using density functional theory (M06 2X) coupled with a group-equivalent approach is described that was used to calculate gas-phase heat of formation (ΔfH°g,298) values for buckminsterfullerene (C60), C70 fullerene (C70), corannulene, coronene, and sumanene. This procedure was also used to calculate exceptionally accurate ΔfH°g,298 values for a variety of single-ring aromatic and 2–7 ring polycyclic aromatic hydrocarbons (PAHs) as well as a large selection of other hydrocarbons and phenols. The approach described herein is internally consistent, and results for C60, C70, corannulene, coronene, and sumanene are in very close agreement with results reported by others who used higher-level computational theory. Statistical analysis of a test set containing benzene and 18 two to seven ring PAHs demonstrated that by using this approach a mean absolute deviation (MAD) and a root-mean-square deviation (RMSD) of 0.8 and 1.3 kJ/mol, respectively, were achieved for reference/experimental ΔfH°g,298 values versus calculated/predicted ΔfH°g,298 values. For statistical analysis of a larger test set containing 235 aromatic and aliphatic hydrocarbons and phenols, a MAD and a RMSD of 1.2 and 1.9 kJ/mol, respectively, were achieved for reference/experimental ΔfH°g,298 values versus calculated/predicted ΔfH°g,298 values.