High resolution solid-state N.M.R.

Abstract

By means of rotations around two axes inclined at zeros (magic angles) of the l = 2 and l = 4 Legendre polynomials, first-order and second-order N.M.R. broadening can be averaged away. Experiments with a double-rotor on the central (1/2 ↔ - 1/2) transition of sodium-23 in polycrystalline sodium oxalate illustrate the elimination of broadening due to second-order quadrupolar effects leading to a thirtyfold increase in resolution compared to magic-angle spinning.