p-π Electron Character Observed through the Anisotropy of ESR in Undoped (CH)x

Abstract
ESR measurements were done in stretched films of undoped cis -rich (CH) x at X band. The anisotropy was observed in linewidth and g value. Both quantities showed maxima when the external field was parallel to the stretch direction of the film and showed minima when the field was perpendicular to this direction. Those features are reasonably explained by the anisotropic property of the carbon p -π orbital and strongly suggest that the ESR center has its origin in the p -π electron in undoped (CH) x .