ELECTRONIC STRUCTURE OF α AND β-PHASE OF POLY (VINYLIDENE FLUORIDE)

ABSTRACT The pseudopotential methods have been employed to investigate the electronic structures of α and β-PHASE poly (vinylidene fluoride). In the energy band structure of β-PHASE PVDF, a large dispersion of the valence band is found only along the chain direction, which agrees well with the angle-resolved photoemission experiments and implies the quasi-one-dimensional nature of β-PHASE PVDF. The large dispersion of the LUOM is caused by H s, C2 s p state mainly. The energy band structure of β-PHASE exhibits anisotropy, while isotropy is found in the energy band of α -phase PVDF.