The energy–density landscape for soft spheres

For soft spheres the number of minima on the potential energy landscape is independent of the volume, and the shape of each basin in the potential energy landscape varies with volume in a predictable way. Two simple assumptions, (1) that the basins are harmonic and (2) that the distribution of basin depths is Gaussian, yield a model for the cold dense states of matter: crystals, glasses, the supercooled fluid and the glass transition. The model agrees with simulation data at temperatures below freezing but fails above the freezing temperature, where the harmonic approximation breaks down.