A THEORETICAL STUDY ON CORRELATION BETWEEN THE STRUCTURES AND ³¹P NMR CHEMICAL SHIFTS OF DICOORDINATED PHOSPHENIUM CATIONS

Abstract

MNDO calculations are performed for studying correlation between the electronic and geometrical structures and ³¹P NMR chemical shifts of dicoordinated phosphenium cations. A simple relationship is introduced to elucidate the ³¹P NMR chemical shifts of the cations from the calculated net atomic charges of the related atoms, Wiberg bond orders between the phosphorus atom and the atoms attached to it, and the bond angle at the phosphorus. The agreement of the calculated numerical results with the experimental data shows that the relationship obtained in this paper is satisfactory for the prediction of the ³¹P NMR chemical shifts of the dicoordinated phosphenium cations.

Key Words:

• ³¹P NMR chemical shift
• Dicoordinated phosphenium cations
• MNDO calculation
• Net atomic charge: Wiberg bond order