Phase transitions in single crystal tubes formed from C60 molecules under high pressure

Abstract: Pure single crystal tubes formed from C60 molecules, with a face-centered cubic (fcc) structure were fabricated by a liquid–liquid interfacial precipitation method using C60 powder. A bulk transition from fcc to a simple cubic structure and a surface transition from (1×1) to (2×2) have been observed around 246K (bulk transition temperature T B) and 214K (surface transition temperature T S), respectively, during the measurement of the temperature dependence of electrical resistance. The initiation of the two transitions under pressure was investigated using a piston cylinder high pressure apparatus and it was found that both T B and T S increase with increasing pressure. And the C60 molecules at the surface of the tube exhibit the same behavior of that in the bulk at a pressure of about 2.1GPa. [Copyright &y& Elsevier]