Effect of size on dielectric constant for low dimension materials

Based on the consideration on size-dependent root of mean-square displacement of vibration of atoms (rms) σ(D), where D denotes the diameter of nanoparticles and nanowires or the thickness of thin films, size-dependent dielectric constants of low-dimensional materials are modeled without any adjustable parameter. The model predicts a decrease or an increase in dielectric constants with drop of D. The predicted results correspond to experimental and other theoretical results for particles and thin films of Si, CdSe, GaAs, H2O and thiol.

Research highlights
► The dielectric constant of low-dimensional materials is modeled without any adjustable parameter.
► The dielectric constant of particles and thin films of Si, CdSe, GaAs, H2O and thiol were predicted by the model.
► The dielectric constants of particles and thin films are decreased or increased with drop of nanocrystals’ size.