Review of
"Encapsulated Nanowires: Boosting Electronic Transport in Carbon Nanotubes"

Review of "Encapsulated Nanowires: Boosting Electronic Transport in Carbon Nanotubes"

Submitted by joegilkes  

March 31, 2022, 11:12 a.m.

Lead reviewer

joegilkes

Review Body

Reproducibility

Did you manage to reproduce it?
Partially Reproducible
Reproducibility rating
How much of the paper did you manage to reproduce?
5 / 10
Briefly describe the procedure followed/tools used to reproduce it

Attempted to reproduce the following results, but using the FHI-aims all-electron DFT code instead of the Quantum Espresso plane-wave DFT code:

  • Electronic band structures of nanowire, nanotube and encapsulated nanowire systems
  • Phonon dispersions of encapsulated system
  • Electron-phonon coupling constants
  • 3rd derivatives of force constants

Started by extracting geometries for the three systems from the QE input files. Ran convergence tests on the encapsulated system to determine the accuracy of basis set that would be required for calculations. Ran geometry optimisations on the three systems and their unit cells. Calculated electronic band structures for the three systems. Used FHI-vibes to calculate phonon dispersion of encapsulated system. Experienced difficulties with this step, so didn't get to reproducing the other two results.

Briefly describe your familiarity with the procedure/tools used by the paper.

Not familiar with Quantum Espresso or phonon calculations.

Which type of operating system were you working in?
High Performance Computing Cluster
What additional software did you need to install?

FHI-aims DFT code already installed on Sulis HPC, had to install FHI-vibes Python package (includes Phonopy package).

What software did you use
  • FHI-aims DFT code.
  • FHI-vibes vibrational analysis package.
What were the main challenges you ran into (if any)?
  • Calculation input files and details were all made to work with Quantum Espresso, so multiple input parameters didn't have any analogues in FHI-aims.
  • No numerical data for electronic bandstructures and phonon dispersions were provided, so comparison to the original results was difficult.
  • FHI-vibes had its own issues with running phonon calculations which took a significant amount of time for rerunning.
What were the positive features of this approach?
  • Managed to reproduce the electronic bandstructures fairly well (nanowire-only calculations were slightly off).
  • Managed to reproduce SOME features of the phonon dispersion (issues could arise from my inexperience at phonon calculations, or just from differences in code between QE and aims).
Any other comments/suggestions on the reproducibility approach?

Documentation

Documentation rating
How well was the material documented?
7 / 10
How could the documentation be improved?
  • Some inconsistencies were present in the provided inputs when compared to the paper and the SI (unit cell dimensions, plane-wave cutoff energy).
  • Structures for the isolated Be nanowire and C nanotube substructures could've been provided, as it wasn't clear whether these had been separately optimised in the paper and this could have caused inconsistencies.
What do you like about the documentation?
  • Would've been very easy (in theory) to directly reproduce with QE, instructions were clear for doing so.
After attempting to reproduce, how familiar do you feel with the code and methods used in the paper?
5 / 10
Any suggestions on how the analysis could be made more transparent?
  • Inclusion of numerical data for electronic bandstructures and phonon dispersions would have been useful for comparison.
  • Inclusion of an analysis/plotting script would've been useful, as creating the same phonon plot with the coupling constants overlaid would've been very difficult.

Reusability

Reusability rating
Rate the project on reusability of the material
6 / 10
Permissive Data license included:  
Permissive Code license included:  

Any suggestions on how the project could be more reusable?
  • Inclusion of all three subsystem geometries as xyz files (considerably more interoperable than geometries inside the QE inputs) would allow better reusability of these systems within other codes.


Any final comments