Involving High School Students in Computational Physics University Research: Theory Calculations of Toluene Adsorbed on Graphene

Abstract

To increase public awareness of theoretical materials physics, a small group of high school students is invited to participate actively in a current research projects at Chalmers University of Technology. The Chalmers research group explores methods for filtrating hazardous and otherwise unwanted molecules from drinking water, for example by adsorption in active carbon filters. In this project, the students use graphene as an idealized model for active carbon, and estimate the energy of adsorption of the methylbenzene toluene on graphene with the help of the atomic-scale calculational method density functional theory. In this process the students develop an insight into applied quantum physics, a topic usually not taught at this educational level, and gain some experience with a couple of state-of-the-art calculational tools in materials research.

Methylbenzenes on graphene

“…We previously reported the results of toluene on graphene, by use of vdW-DF1, obtained by visiting high school students who worked in a research project in our group [27]. For time reasons the students used a lower quality on the convergence parameters, they used the 'corner' orientation of the methyl H-tripod, and they did not explore the energy landscape of various positions and orientations of toluene on graphene.…”

“…In Ref. [27] we estimated the zero-point motion of toluene to be just a few meV, which we can therefore ignore here.…”

“…[27] we tested the convergence by using only 17% of the grid points for toluene on graphene, along with the restriction to simple Γ-point sampling in k-space. These rather significant changes to the accuracy resulted in a total of only 20 meV change in adsorption energy, compared to the same calculation carried out at the accuracy used in the present article [27]. The present grid point choices are therefore sufficient.…”