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Dispersion-corrected Hybrid DFT with FHI-aims

Welcome to this tutorial on how to use the FHI-aims code for simulations of dispersion-corrected hybrid DFT.

This tutorial was developed by Konstantin Lion, Sebastian Kokott, James Green, Andrey Sobolev and Volker Blum.

In order to successfully execute this tutorial, you should also have access to the two primary community resources of the FHI-aims project:

Any user of FHI-aims is encouraged to request access to both resources (please follow the instructions at https://fhi-aims.org/get-the-code).

All files related to the tutorial, including solutions, can be found at https://gitlab.com/FHI-aims-club/tutorials/dispersion-corrected-hybrid-dft.

A current copy of the FHI-aims manual can be found at https://aims-git.rz-berlin.mpg.de/aims/FHIaims/-/jobs/artifacts/master/raw/doc/manual/FHI-aims.pdf?job=build.manual.

And yes, FHI-aims is a community code. Without its large community of contributors, FHI-aims would not exist. We are immensely grateful to the very large number of individuals who have contributed to the code over time and who continue to push it forward.

The Objective and the Case Study

This tutorial introduces FHI-aims and its capability to simulate dispersion-corrected DFT calculations at the GGA and hybrid density functional level. We will demonstrate how to run and analyze these calculations for two highly relevant use cases in academia and industry, namely crystal structure prediction for molecular crystals and the analysis of properties for organic-inorganic perovskites.

For these questions, given a reasonably powerful computer, FHI-aims has the large advantage that it can address rather large structure sizes in an achievable fashion, including with hybrid density functionals for over 1,000 atoms (again, on a large computer), all-electron and without any significant approximations in the underlying numerical implementation.

There is much more we could be doing: Vibrational corrections, reaction pathways, molecular dynamics, visualization of electronic levels, various forms of "computational spectroscopies". All this can be done with FHI-aims but is not within reach of this few-hour tutorial.

Prerequisites

  • Users of this tutorial should have a sufficiently good understanding of the Unix command line.

  • It is similarly important to understand how to transfer files between a remote supercomputer and a local computer with a display. Graphical data visualization is an essential part of any scientific analysis. Being comfortable with data visualization at all steps of a simulation is a critical skill, without which a meaningful scientific analysis can usually not be conducted.

  • Users should also understand how to manipulate and extract data extraction from text files.

  • Users should have access to a sufficiently powerful high-performance computer, typically more than one node, with fast interconnect (not Ethernet).