The colloids that were used for the model: particles, each with a diameter of approximately 150 nm, suspended in water. The solid nucleus consists of the plastic polystyrene, the surrounding shell of a thermosensitive poly(N-isopropyl-acrylamide) network. By lowering the temperature, each individual particle’s volume—and, by definition, its packing density—can be increased. Photo: HZB/M. Siebenbürger
Many solids are produced from melting, a process that creates complex internal stresses as the material cools. Until now, our understanding of the unique characteristics exhibited by the condition of the glass as compared with a tough molten mass has been spotty. A collaboration of several research teams in Europe has recently offered a surprisingly simple model to explain the difference between glass and molten materials. Read/Comment
