Solid C70: Anisotropic Molecular Rotation and Orientational Ordering Transition

Abstract
13 C NMR (nuclear magnetic resonance) in C 70 solid was observed between 77 K and 340 K. Clear evidence of a phase transition around 280 K and anisotropic molecular rotation was found in a sublimed C 70 solid with purity of more than ∼ 99%. It was observed that the sample quality significantly affects the C 70 molecular dynamics.