Abstract: A cylindrical body such as a rotor structure containing a sample for an NMR experiment has its axial direction making a selected non-zero angle &phgr; with a predetermined Z-axis. In order to establish a magnetic field such that its component in the Z-direction varies linearly along the axial direction of the cylindrical body, a pair of coil elements which are serially related and are in an electrically anti-parallel relationship are provided on mutually parallel planes so as to overlap each other as seen perpendicularly to these parallel planes. The angle between the normal line to these parallel planes determining the orientation of the coil elements and the axial direction of the cylindrical body should be nearly equal to 2&phgr;−90°, based on the known property of a tilted Maxwell's pair, but may be different by an experimentally determinable small angle.

Abstract: An NMR probe, lacking electrical balance in respect of the RF coil thereof, includes a conducting shield of axial extent greater than &lgr;/4 from the ground plane closure of said shield of the probe (&lgr; being the highest resonant frequency of interest), the components of the probe other than the coil being confined to the axial region less than &lgr;/4 from the ground plane and spaced apart from the shield.