AN ANALYSIS OF NMR SPINNING SIDE-BAND OF HOMONUCLEAR 2-SPIN SYSTEMS USING FLOQUET THEORY

NMR spinning sidebands for homonuclear two-spin systems are described using Floquet theory. The variation of asymmetry observed in J-split doublets from sideband to sideband was found to depend on molecular parameters such as the internuclear direction, the orientation of chemical-shift tensor axes, and the absolute sign of the J-coupling constant. These parameters for the C-13 spin pair in sodium acetate were determined by simulating the experimental spinning sidebands observed under the magic-angle spinning condition. The calculated sideband patterns in the off-magic-angle spinning spectra are also illustrated; these were found to exhibit fine structure sensitive to the spin parameters.