Surface-charge-induced reversible phase transitions of Bi nanoparticles.

Much of the interest in nanostructured materials originates from the challenge to find materials with properties that are substantially different from those of the same materials on a larger scale. New dielectric, [1] ferromagnetic, [2] catalytic, [3] and other properties are indeed being realized. Of particular interest are nanoparticles that exist in new structures, metastable structures, or known structures extended beyond the composition or stability ranges of ordinary bulk materials.