Crystals through the looking glass

Crystalline, amorphous and, recently, quasicrystalline – those are the phases of solid matter we all know. But US based scientists have now added another to that list. Whereas quasicrystals show short range order but long range disorder, this new phase is amorphous in the short range but over larger ranges becomes ordered and crystalline.

Lin Wang, at the Carnegie Institution of Washington, was investigating the properties of C₆₀ solvated in m-xylene, as solvated fullerenes exhibit tunable electronic properties. In a diamond anvil, Wang subjected the mixture to pressures up to 60GPa, pressures at which pure C₆₀ collapses into amorphous carbon. The solvated buckyballs, however, did something different.

In fact, the C₆₀ molecules collected together into amorphous clusters, held together by solvent molecules, and x-ray diffraction shows the material had long range order. The finding may suggest ways of creating strong, carbon-based, materials with tuned physical properties.