Electron delocalization in poly(aniline).

The appropriate quantum-mechanical description for electron- conducting polymers hinges upon whether behavior is better explained with delocalized wavefunctions, the band-model approach, or by localized states confined to small segments of the polymer. Our previous electron-spin-resonance studies of poly(aniline) were best understood through an energy band description. In this paper we examine theoretically and experimentally the ESR, voltammetric, and spectroscopic properties of poly(aniline) and its shortest oligomer, N,N'-diphenyl-p-phenylenediamine. With an empirical Hamiltonian matched to the oligomer's hyperfine structure, we find it possible to describe the properties of both oligomer and polymer, supporting the validity for a delocalized description. Calculations were expeditiously accomplished with a PC 6300 using eigenfunction and FFT subroutines.