Theoretical calculations on C30H12 bowl-shaped hydrocarbons: NMR shielding constants, stability, and aromaticity

Abstract

Density Functional Theory (DFT) calculations at the B3LYP/6-31G* level have been performed on four bowl-shaped polyaromatic hydrocarbons of C30H12 molecular formula (1-4) showing C3 (1), C2υ (2 and 4), and C2h (3) symmetries. The geometrical and electronic properties of the compounds studied have been analyzed to explain their relative stability. NMR chemical shifts parameters for the atoms and Nucleus Independent Chemical Shifts (NICSs) for the rings were calculated using the GIAO method. The 13C and 1H chemical shifts calculated are in very good agreement with the experimental data. © 1999 John Wiley & Sons, Inc.