強誘電性ポリフッ化ビニリデン I 型結晶の電子状態

Abstract

In order to gain an insight into the characteristics of solid poly(vinylidene fluoride) (PVDF), we have carried out the quantum chemical calculation for the relationship between the form I crystal structure of ferroelectric PVDF with an all-trans conformation and the electronic structure using various ab initio DFT methods in the solid state computational tool CRYSTAL. On the basis of the calculated results, the lattice constants of the form I crystal structure and chemical bond parameters for PVDF were evaluated. As a result, the calculations with the PBE0 hybrid functional agreed with the experimental X-ray diffraction analyses for the form I crystal structure of PVDF within the margin of error of ±1.4%. Further, the chemical bond parameters such as C-F bond length and F-C-F bond angle etc. were determined. Consequently, the PBE0 hybrid functional was found to be useful for the computational prediction for the solid state of PVDF.