Related Experiment Video
Updated: Mar 17, 2026

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
Effect of the van der Waals interaction on the electron energy-loss near edge structure theoretical calculation
Hirotaka Katsukura1, Tomohiro Miyata1, Kota Tomita1
1Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan.
Abstract:
The effect of the van der Waals (vdW) interaction on the simulation of the electron energy-loss near edge structure (ELNES) by a first-principles band-structure calculation is reported. The effect of the vdW interaction is considered by the Tkatchenko-Scheffler scheme, and the change of the spectrum profile and the energy shift are discussed. We perform calculations on systems in the solid, liquid and gaseous states. The transition energy shifts to lower energy by approximately 0.1eV in the condensed (solid and liquid) systems by introducing the vdW effect into the calculation, whereas the energy shift in the gaseous models is negligible owing to the long intermolecular distance. We reveal that the vdW interaction exhibits a larger effect on the excited state than the ground state owing to the presence of an excited electron in the unoccupied band. Moreover, the vdW effect is found to depend on the local electron density and the molecular coordination. In addition, this study suggests that the detection of the vdW interactions exhibited within materials is possible by a very stable and high resolution observation.
Related Concept Videos
Van der Waals Interactions
Van der Waals Equation
First, the attractive forces between molecules, which are stronger at higher densities and reduce the pressure, are considered by adding to the pressure a term equal to the square of the molar density multiplied by a positive coefficient a. Second, the volume...
The de Broglie Wavelength
The Van der Waals Equation
π Electron Effects on Chemical Shift: Overview
Fermi Level Dynamics
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...

