X-ray Quality Geometries of Geodesic Polyarenes from Theoretical Calculations: What Levels of Theory Are Reliable?

Computational methods for calculating molecular geometries
have not been well calibrated heretofore against X-ray data
for bowl-shaped polycyclic aromatic hydrocarbons (PAHs).
The analysis presented here capitalizes on a rare opportunity provided by corannulene to account explicitly for
molecular distortions from crystal packing forces. Within the
error limits of an extensive X-ray data set, B3LYP/6-31G*
calculations were found to correctly reproduce all of the
experimental bond distances and bond angles. The reliability
and shortcomings of geometry calculations at other levels
of theory are enumerated.