Abstract: There is disclosed high-resolution NMR spectroscopy in solids. Magic angle spinning and cross polarization are used in conjunction. The sample is rotated by a spinner at a high speed about an axis oriented at the magic angle 54.degree.44' with respect to the static magnetic field. Under this condition, a 90.degree. pulse is applied to abundant nuclear species, such as .sup.1 H that is coupled to dilute nuclear species, such as .sup.13 C. Then, a spin-locking pulse or pulse sequence is applied to the abundant nuclear species. An observing pulse or pulse sequence is applied to the dilute nuclear species. The free induction decay signal from the dilute nuclear species is detected. The spin-locking pulse or the observing pulse is amplitude-modulated at a low frequency.

Abstract: A capacitor stick having a base electrode on whose tip is installed a chip capacitor is disclosed. The chip capacitor is insulated from the base electrode. A compensating coil is inserted between the base electrode and chip capacitor, and a series resonant circuit regarding a decoupling high frequency is composed of the chip capacitor and compensating coil.