Nanocluster formation in electron-irradiated Li2O crystals observed by elastic diffuse neutron scattering.

Previous work performed on electron-irradiated Li2O crystals has demonstrated the simultaneous formation of two populations of colloids of metallic lithium, one is associated with oxygen bubbles and a typical size of >10 microm, while the other one consists of nanoclusters in the range of <10 nm. In the present neutron scattering investigation these small colloids are characterized in detail based on a thorough analysis of distortion scattering around Bragg peaks. It is shown that the small lithium colloids are slightly elongated precipitates with typical dimensions of around approximately 5 nm. For the large lithium colloids a well-defined orientation relation with respect to the Li2O matrix has been determined.