Atomistic Nature of Amorphous Graphite

TL;DR

This study investigates the structural, electronic, and vibrational properties of amorphous graphite, revealing its unique features compared to crystalline graphite and amorphous carbon, and providing insights into its potential experimental signatures and thermal conductivity.

Contribution

It provides a comprehensive analysis of amorphous graphite's structure, electronic states, vibrational modes, and thermal conductivity, highlighting its distinct properties and potential experimental fingerprints.

Findings

Amorphous graphite has a distinct structural order compared to crystalline graphite.

The vibrational density of states offers a testable fingerprint for the material.

Thermal conductivity of amorphous graphite is approximately 0.85 W/cm·K at room temperature.

Abstract

This paper focuses on the structural, electronic, and vibrational features of amorphous graphite [R. Thapa $\textit{et. al.}$, Phys. Rev. Lett. 128, 236402 (2022)]. The structure order in amorphous graphite is discussed and compared with graphite and amorphous carbon. The electronic density of states and localization in these phases were analyzed. Spatial projection of charge densities in the $\pi$ bands showed a high charge concentration on participating atoms in connecting hexagons. A vibrational density of states was computed and is potentially an experimentally testable fingerprint of the material. An analysis of the vibrational modes was carried out using the phase quotient, and the mode stretching character. The average thermal conductivity calculated for aG was 0.85 Wcm$^{-1}$K$^{-1}$ and 0.96 Wcm$^{-1}$K$^{-1}$ at room temperature and 1000 K respectively.