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With the advent of more computational power than ever in the recent years, interest in in silico design of interesting compounds has grown as well. I am wondering about the state of the art for the case of designing novel materials:

  • What methods are commonly used (DFT, semi-empirical, more / less expensive)?
  • What size of lattices is one able to treat in high-througput screening approaches?
  • What is the effort in terms of runtime one needs to put in?
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2 Answers 2

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After a little research I found a great article [1], which provides a good overview to what I asked above in Figure 2. Summarising in a table:

Method effort reliability system size
Interatomic potentials high high/low* $10^8$
Linear-scaling DFT high medium-high $10^6$
Tight binding high medium-high $10^6$
LDA DFT low medium-low $10^3$
GGA DFT low medium $10^3$
GGA+U DFT low medium-high $10^3$
Hybrid DFT low high $10^2$
GW high high $10^1$

* high for geometries and energetics, but low for excited states or the dielectric function

where effort refers to the manual effort from the researcher, reliability gives the reliability of the method and system size is the typical system size in the number of atoms. In the table I am providing a condensed (and maybe biased) overview, focusing on properties such as geometry, energetics, dielectric function, excited states or bandgap. See [1] for the full details.

References

[1] K. T. Butler, J. M. Frost, J. M. Skelton, K. L. Svane and A. Walsh. Chem. Soc. Rev., 2016, 45, 6138. DOI 10.1039/c5cs00841g

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    $\begingroup$ Since this thread just got bumped, I want to point out GGA+U is definitely not low effort and I wouldn't say its more reliable than GGA or LDA. $\endgroup$ Jan 19, 2022 at 1:00
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I am sure there are A LOT of authors publishing papers to answer this very question. Mainly because the theories employed have face a paradigm since "one-size-doesn't-fit-all".

Here are the variables that affect this use of a certain method:

(i) Molecular models or periodic solids

(ii) Chemical Accuracy (energies with accuracy of < 1kcal/mol) - e.g. in polymorph stability such as crystal structure prediction or molecular solids

(iii) Electronic structure (band gap/density of states/ band structure/excitonic effects) can be calculated using PBE+U (or PBE+D3+U) that is Fast vs Hybrid (PBE0/HSE06/etc.) or quasiparticle GW calculations that can be quite slow

A good read on theoretical comparisons:

(i) Philosophical+technical: https://science.sciencemag.org/content/355/6320/49/tab-figures-data

(ii) Technical benchmarking of a recent density functional across various model solids: https://journals.aps.org/prx/abstract/10.1103/PhysRevX.6.041005

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