In this application we will conduct the first detailed study of the structure of glassy metal-ammonia systems ? so-called Ogg glasses, named after the person who first proposed them in 1946. To start this programme of research we aim to determine the structure of the Li and Na based Ogg glasses at compositions of 4 and 12 MPM. From this we hope to learn how the glass and liquid structures differ, and also the temperatures at which any structural changes take place. Note from Figure 1 that the ?escape route? from the glass will involve phase separation into solid ammonia and concentrated metallic metal-ammonia solution. Neutrons are needed for this work as we will use H/D and N/15N isotope labelling to resolve any subtle structural changes. We propose to use SANDALS for this experiment because we do not anticipate any small angle scattering (NIMROD would cover this base if available).