Conduction-electron spin resonance in small particles of sodium

Abstract

Results of conduction-electron spin-resonance (CESR) measurements on small sodium particles formed in x-irradiated sodium azide are interpreted according to a simple model which includes the effects of a broad particle size distribution and the presence of surface spins. Estimates of line broadening due to exchange interaction between the surface spins and the conduction electrons are found to be consistent with experimentally observed broadening at helium temperatures. A signal observed at the sodium CESR $g$ value for very low incident microwave power level is considered to represent a hyperfine envelope of CESR signals from particles exhibiting quenched spin-lattice relaxation resulting from discreteness of the conduction-electron energy levels.