Modification of dielectric properties of C_(60), C_(70) and C_(84) thin films by oxygen absorption

摘要

C_(60) and higher fullerenes are efficiently produced by the J x B gas-arc method. From the produced soot, C_(60), C_(70) and C_(84) are extracted and purified by the liquid chromatography method. C_(60), C_(70) and C_(84) thin films with a thickness of 1-4 μm are produced by the vacuum sublimation method, and their dielectric properties are investigated. Both the real and imaginary parts of the dielectric constants of C_(60), C_(70) and C_(84) are very high at a low frequency (f = 120 Hz) and they monotonically decrease with time when the films are exposed to air. After sufficient absorption of oxygen, these dielectric constants become almost the same.