Field Gradients at the Deuteron in Molecules

Abstract

A survey of the observed quadrupole coupling constants of the deuteron is presented. It is concluded on the basis of calculations that the field gradients at hydrogen nuclei will be positive in almost all molecules. The simple wave functions greatly underestimate the field gradients of the bonding electrons. A good part, but not all, of the discrepancy, previously noted by White, can be removed with the use of a contracted charge distribution and ionic character. The wave function of Ellison and Shull gives a very bad description of the field gradients at the deuterons in D₂O but the experimental data indicate the direction for future improvement. The field gradients at deuterons remain attractive quantities for characterizing the charge density in bonds involving hydrogen atoms.