Ring current effects on nuclear magnetic shielding of carbon in the benzene molecule

Abstract

The differential Biot-Savart law of classical electrodynamics was applied to develop a ring current model for the magnetic shielding of the carbon nucleus in benzene. It is shown that the local effect of the π currents, induced by a magnetic field normal to the molecular plane, on the σC out-of-plane shielding tensor component vanishes. However, approximately 10% of σC is due to the shielding contributions from π current density in the region of the other carbon atoms. Magnetic shielding density maps obtained via quantum mechanical procedures confirm the predictions of the classical model.