Electrostatic properties of two-dimensional C60 polymer thin films under an external electric field

Abstract

Electrostatic properties of different C60 thin films under external electric fields have been investigated from first-principle total-energy calculations. Density functional theory calculations combined with the effective screening medium method reveal that the electrostatic properties of C60 thin films in an electric field strongly depend on the arrangement and conformation of the C60 molecules. The relative permittivity across the thin films exhibits clear a positional dependence resulting from the π electron distribution within the films. An electrostatic polarization is uniformly induced by weak electric fields, typically 0.1 V nm−1, because of the semiconducting electronic structure of the thin films, whereas the polarization is highly concentrated in the outermost C60 layer under strong electric fields of 0.5 V nm−1.