Spectroscopic evidence for large (<<1 mu m) lithium-colloid creation in electron-irradiated Li2O single crystals

We have created lithium metal colloids by electron-irradiating single crystals of lithium oxide near 0 degrees C. The striking feature is the observation of two kinds of colloids manifesting, themselves as two EPR metallic lines, the narrow line corresponding to small metallic clusters (size <1 mu m) and the broad one associated with large metallic colloids visible by optical microscopy (similar to 20 mu m), The latter are also observed by NMR. A further indication for the presence of colloids of different types is the differing recovery behavior of the two EPR lines in an annealing treatment.