# Tag Info

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(Disclaimer: As one of the main authors of a Julia-based DFT code, DFTK, my opinion is definitely biased) The community of people employing Julia for materials modelling is still small, but a couple of programs exist. Probably a good overview gives https://github.com/svaksha/Julia.jl/blob/master/Chemistry.md. Many projects have only started within the last ...

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In an era of ab initio methods and many-body methods like the $GW$, there is not too much room for methods like the extended Hückel model to be the main method in any particular field of materials modeling. However, the method is still very much appreciated by the solid-state community particularly for it's accessibility. It is especially popular with those ...

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2003: Book chapter by Karen Hallberg. 2004: Reviews of Modern Physics by Ulrich Schollwoeck (2818 current citations). 2006: Advances in Physics by Karen Hallberg. 2008: JCTN: by Gabriele De Chiara and co-workers. 2011: ARPC: by Garnet Chan and Sandeep Sharma (426 current citations). 2014: The European Physical Journal D by Sebastian Wouters and Dimitri Van ...

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Yes, there are! One early example that's still in use today is the Universal Structure Predictor: Evolutionary Xtallography (USPEX) method. You can find many "success cases" on their website if you're curious. The First-Principles-Assisted Structure Solution (FPASS) and Prototype Electrostatic Ground States (PEGS) methods are a couple of other codes used for ...

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Here is state of the art research: Smith J.S. et al, Approaching coupled cluster accuracy with a general-purpose neural network potential through transfer learning, July 2019 Nat. Commun. 2019, 10 (1), No. 2903, PMID: 31263102 Computational modeling of chemical and biological systems at atomic resolution is a crucial tool in the chemist's toolset. The ...

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One area where the extended-Huckel method continues to see use is to form the initial guess for an SCF calculation or even just a more accurate semi-empirical method. While most electronic structures packages use the Superposition of Atomic Densities (SAD) guess as the default, the option is available in almost all of them and Psi4 uses it as the default for ...

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A few years ago, I was fascinated by the news of the discovery of a new Carbon allotrope based on first-principle simulations by using USPEX software described here. Or particularly this article: Zhu Q., Oganov A.R., Salvado M., Pertierra P., Lyakhov A.O. (2011). Denser than diamond:ab initio search for superdense carbon allotropes. Phys. Rev. B83, 193410, ...

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As evident from the name, Materials Modelling (or Computational Materials Science as it is sometimes called) lies at the intersection of materials science and computational engineering. To answer this question, the level of education required depends entirely on what one intends to do with materials modelling. Materials science is quite interdisciplinary, ...

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I would recommend to start with Computational Materials Science: An Introduction by June Gunn Lee, The book starts from the basics and covers Molecular Dynamics and DFT featuring DFT exercises using VASP, Quantum Espresso and Medea-VASP. It is undergraduate level introduction to the subject Materials Modelling Using Density Functional Theory: Properties and ...

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There are several such studies, particularly focusing on the machine-learning of critical temperatures. "Machine learning modeling of superconducting critical temperature" "An acceleration search method of higher T c superconductors by a machine learning algorithm" "Can machine learning identify the next high-temperature superconductor? Examining ...

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There are two considerations guiding the choice a basis for orbital expansion: 1. Compactness; 2. Efficiency of computations. There are two common choices for basis functions (A) Gaussians and (B) Plane waves. Both of those allow for the most efficient way to evaluate the integrals needed to construct the Fock matrix (i.e. second derivative for kinetic ...

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Assuming you are interested in pursuing plane-wave periodic DFT, there is a clear best answer in my opinion and that's "Density Functional Theory: A Practical Introduction" by Sholl and Steckel. For a relatively complex topic, they truly manage to accomplish the goal of making this a practical introduction. As they say in the intro, "you don't need to learn ...

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Disclaimer: I am a developer of the Fleur code. I hope that I don't put too much bias into this answer. At least I try to not do that... When you want to solve the Kohn-Sham equations you have the problem that the potential has singularities at the atomic nuclei. There are different ways to deal with this. On the one hand you can make the pseudopotential ...

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Unfortunately, I don't believe such a resource exists. One should keep in mind that it's not just a matter of a single U value for every metal, of course. The "best" empirical U value will depend on the property of interest. Perhaps more problematic, not every metal environment is made equal. Different oxidation states, coordination environments, and overall ...

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I would like to expand on Roman Korol's answer a bit. He already lists GTO's and plane waves as they are the most common kind of basis functions. These are characteristic for the underlying models by which they are motivated. GTO's approximate the solutions to the hydrogen atom and are thus atom centered functions used for molecules. Plane waves on the other ...

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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 ...

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A good place to start is the classical Allen-Tildesley book, Computer Simulation of Liquids, which covers the basics of molecular dynamics that hasn't really changed in a long time. The book can be supplemented with literature, such as review articles for whatever it is you want to do. Software manuals are also often quite useful to find out how things are ...

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Another extremely popular resource is Frenkel and Smit's textbook "Understanding Molecular Simulation". It covers all basics on molecular dynamics, Monte Carlo, some common enhanced sampling methods, free energies and it even derives the Ewald summation. This is basically a book that doesn't shy away from messy derivations and it gives you a lot of ...

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Great question! Protein folding has been in open question for decades. Just recently, there's been a lot of discussion regarding DeepMind's AlphaFold project, which was discussed at length on our very own site here. My answer will be complementary to the one above, but the references I will provide will be closer to the physics side of the problem. First ...

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This answer is adopted from the book Materials Modelling Using Density Functional Theory: Properties and Predictions by Feliciano Giustino Greeley et al. (2006) searched for potential replacements for Pt as catalyst in hydrogen production using DFT calculations. One of the most promising alloy was an hypothetical material BiPt. The material was synthesized ...

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If you are familiar with the Behler-Parrinello symmetry functions implemented in AMP, you may be interested in seeing how they compare to other atom-centered representations in terms of speed and accuracy. Marcel F. Langer, Alex Goeßmann, and Matthias Rupp have recently released their benchmarking efforts including the symmetry functions, the Many-body ...

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This is Steve Plimpton. So far as I know there is no official DYNAMO website or download location. The code long pre-dates the popularity of source code "repositories". It was developed by Daw and Foiles (mentioned in the thread), two or the originators of EAM potentials. That said, I do have a tarball I can send you if you contact me via my work email - I'...

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The missing semester: An MIT Course For a beginner in the field, most often the difficulty would be in working with unix-like environments, which is the only way to access many of the matter modeling software and probably the most convenient way to analyse the outputs of the calculations. And this is often learned the hard way by searching the internet on ...

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I know of at least one place, where it is relatively common to use the extended Hückel theory in practise: in generating initial guess orbitals for further electronic structure calculations. The most popular example I can think of is Turbomole, see its manual (pdf, chapter 4.3, p. 75). They claim that the starting vectors are better than a core Hamiltonian ...

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Thomas has listed some great resources. Let me add some more, mostly materials science-related ones: NOMAD has regular workshops, "Hands-on DFT and beyond", and the recordings from 2017, Berlin are uploaded to Youtube: https://www.youtube.com/playlist?list=PLbgFiRV2JFy-VQ3D6cJjn5jkXmAsjQPiT Slides of the more recent workshops can be found Barcelona (2019): ...

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1. Online course on Computational Materials Physics by Prof. Stefaan Cottenier All content is offered via prerecorded videos. Each video comes with a task, and after submitting the task there is in many cases either automated feedback or peer feedback. At any other time of the year, you can still study this course in a self-paced way. There is the ...

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I think that it is not the education per se (a Masters or PhD in Physics or Chemistry, for example), but the set of disciplines you take that will help you to better understand and work in the Materials Modeling area. Courses like Classical Mechanics, Electromagnetism, Quantum Mechanics, Statistical Mechanics and Solid State Physics are fundamental. Also, ...

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There is a page on the Sandia labs website that includes download links for all the software developed by Steve Plimpton. It sounds as if he reimplemented all the functionality of DYNAMO into a program called ParaDyn (the para denoting that it was modified to run in parallel). Alternatively, the site makes it sound as though almost all the features of DYNAMO ...

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An starting point can be the following review paper: Designing meaningful density functional theory calculations in materials science—a primer. Ann E Mattsson et al. 2005 Modelling Simul. Mater. Sci. Eng. 13 R1 (DOI: 10.1088/0965-0393/13/1/R01) As the authors state: Our primary goal is to provide practical guidance in the design of meaningful DFT ...

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Another slightly less commonly seen basis are the sinc functions, which are related to plane waves, but come at the problem from the perspective of a position, rather than momentum, space. They are delocalized functions, but sharply peaked at their center point and zero valued at the centers of other sinc functions, effectively partitioning space into a grid....

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