# Tag Info

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I just joined this community to answer you after I've randomly seen your post, because I think there are a couple of important variables you may want to consider: your feelings and your intuition. You can rationally consider many variables, but you are very young and there may be topics that you like now that you will consider boring in the future, and the ...

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As someone who did his undergrad in Canada, PhD in UK, and acquired post-PhD research experience in Japan, Singapore, USA, Germany, and again in Canada: I can say that the dilemma you're facing is a major disadvantage of the undergrad UK system. The UK system has many advantages too! But the flexibility is better in other countries such as Canada and US. ...

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Elk Free, and can be redistributed or modified under the terms of GPU General Public Licesence. Well explained on this webpage. Well documented in this PDF file. Interacts with the following codes: Wannier90 Phonopy NOMAD Libxc ASE DGrid Elk optics Analyzer PyProcar Advertised in a few places as being focused strongly on being simple and easy to develop. ...

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I think the naming conventions are standardized and people computing band structures employ them directly. I will break down the high-symmetry points for a 2-D brillouin zone and post very good references for you to explore 3-D BZs. Take a rectangular Brillouin zone as the one depicted below: The center of the brillouin zone is unequivocally marked as $\... 12 As a Bachelor in Physics that do research in Material Science and in Drug Development, I have to recommend you to go for the Physics degree. Also, you have to be aware about the type/specialization of the Physics course. For example, my undergrad Physics course was focused in Solid State, so, we had Quantum Mechanics, Solid State Physics and Crystallographic,... 11 I'm a fellow Brit who did Chemistry as a first Degree, before moving into a hybrid chemistry/statistics PhD and now works as a software engineer. My suggestion is not to get too caught up in the exact subject that you are studying and consider the areas you are enjoying the most and find the course that fits your interests, regardless of course title. A good ... 11 This depends a lot on how the DOS is calculated. I don't know the options one has for this when using VASP or SIESTA, but I am aware of different approaches. The central problem is that you don't know which state at a certain k point is "connected" to some other state at another k point. When calculating a DOS you have to integrate over the ... 11 Its a bit more on the physics side but for solid-state physics I quite liked the "The Oxford Solid State Basics". Its a very good intro because its quite short so you can actually go through most of it unlike some others which are too long so you only end up reading a fraction of it. What is also another great thing about is that the lecture series ... 10 An Engineer's perspective: I started with a Bachelor's in Mechanical Engineering, and then moved to a Master's in Materials Science and Engineering. Worked for 4 years in the industry, and now came back to do a PhD in Materials Engineering. If I could go back, I would definitely do the same thing, but maybe invest more time in Physics along the way. Basic ... 10 Some people do: In this paper there is a system coupled to a bath of Morse oscillators rather than a bath of harmonic oscillators, but it is not exactly solvable, they used a numerical approach called mctdh. When it is said that the Morse potential is "exactly solvable", what it means is that you can solve the vibrational Schroedinger equation for ... 10 This website CompMatPhys is an excellent starting point. It is free and self paced, and the videos are really good. It was linked by Jack, as an answer to a different question. I will find it and update and link to it as well so that Jack gets his due credit. 10 1. Is it possible that the energy gap of the material is direct in the bulk but indirect in the slab? Yes, this is possible (as is the reverse). The 2D slab does not have the same symmetry as the full 3D slab, and there is no requirement for the conduction band minima and valence band minima to be at the same points in reciprocal-space. As you make the slab ... 9 Is that related to crystal splitting? Yes. In case there are any doubts, the caption to the figure does make it clear that it's related to crystal field splitting, "(d) The splitting of d orbitals under the trigonal prismatic crystal field". How may I understand this partition of five d-orbitals under such a trigonal prismatic geometry? If you ... 9 Realizing this Hamiltonian in a natural material I cannot imagine a material in which all nearest-neighbor spin-spin interactions can be adjusted arbitrarily at the same time. Spin-spin couplings that are stronger when the spins are closer together, and weaker when the spins are farther apart, can be adjusted by moving the spins relative to each other; so ... 9 Elk / EXCITING Like @Nike Dattani suggested, Elk is an open-source well-documented FP-LAPW DFT package. Also, LAPW stands for Linearly-Augmented Plane Wave. Singh's book is an excellent introduction for this topic. (Disclaimer: I'm currently developing an extension to Elk / EXCITING to compute response functions and estimate Hubbard model parameters using ... 9 I'm not working in material sciences but as a (particle) physicist I came into touch with solid physicists a lot. To elaborate: In particle physics, one of the main components is usually the scintillator crystal which is a very high advanced material. The material for it for an upcoming particle accelerator was entirely researched by our neighbour working ... 9 I studied physics and three of my family members studied chemistry. Don't worry too much about the choice. Any of those subjects will provide you with interesting study and enough career opportunities. Any scientific subject gets more interesting the harder you look at it (even Biology). You don't need lots of career opportunities, you only need a few. ... 8 I will first take a generic view-point and then quote some examples in condensed matter & materials modeling. Time-reversal symmetry is one of two discrete symmetries usually discussed in the context of condensed-matter, the other being Parity(Inversion). The simplest way in which this concept is presented is a transformation :$ t \rightarrow -t . ... 8 Another way to explicitly break time-reversal symmetry is by applying circularly polarized light. Under time reversal, left circularly polarized light transforms to right circularly polarized light, and vice versa. One way to see this is to note that circularly polarized light is an eigenstate of the spin angular momentum operator, which is odd under time ... 8 The sisl python package might be useful to you. It has: Tools to build hamiltonians with user-defined basis orbitals. A very high level API to visualize the most common analysis from your hamiltonian (bands, PDOS, wavefunctions, etc...). Lower level APIs to customize your analysis as you wish. Here's an example of how you might define a tight binding ... 7 I understand that you are trying to implement cell lists. For orthogonal unit cell (or even better - cubic) the cells that subdivide the unit cell are nicely aligned with the unit cell. Wikipedia has this illustration: For a non-orthogonal unit cell the calculations are more complex, but you can still use a rectangular box divided into cells. Here is an ... 7 Disclaimer: These are just some observations; I don't claim to know the answer to this question. There's a lot of overlap between both camps, but I think people tend to stick mostly with one kind of system, in their research. You may be largely correct - I'd just like to point out that if we are looking at the simulation engines (rather than what people do)... 7 You should take Binh Tien's advice for the continuity part of your problem. It has also been answered somewhat here: How to ensure a smooth band structure? As for the gap issue, adding to Phil Hasnip's answer, a similar question has also had several proposals for answers here : How to generate the high symmetry paths for band structure calculations? These ... 7 In this case,\mu$refers to the chemical potential. The reason it is given as$\mu-E_f\$ is simply to highlight that the "zero" has been set to the Fermi-level of the reference calculation (usually, undoped bulk). In a pseudopotential calculation, there is an arbitrary, pseudopotential-dependent offset to the energies, so their absolute values are ...

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I think one thing missing from other commenters here is the fact that your university and PhD concentration diminishes in importance and relevance as you get older. This begins almost immediately out of your PhD. Nowadays, a successful researcher will work inside a highly interdisciplinary team and pick up skills in additional areas. You'll start out ...

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I think Natural Sciences could be a good fit for you. I studied almost the same A Levels you did and couldn't decide whether I preferred Physics or Chemistry. Studying Natural Sciences allowed me to take courses in both, and to choose the areas I liked most and leave out the ones I didn't It's worth bearing in mind that these subjects change in content when ...

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Being great at what you like doing will open far more doors for you. You will find that there is a lot more variety of jobs than you think, and you will find interesting opportunities by being at the top of your field. It sounds like you will really excel at chemistry, and being in a field you are excited about is a lot better (Personal satisfaction and for ...

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Even in treating molecular vibrations, the Morse potential is not always the best, because: There's cases where the potential is more "harmonic" than "Morse-like", for example in the asymmetric stretching of water. It is the same case in solid state physics: considering the most crude approximation that we fix all the atoms in a solid ...

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In general the best resource for details about VASP tags and their use is the VASP wiki page. For the virtual crystal approximation the relevant tag appears to be "VCA" and the corresponding wiki page is here. I have never used the virtual crystal approximation, so cannot speak about its merits. However, I would highlight the text at the bottom of ...

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Questaal Questaal is a suite of electronic structure programs. The codes can be used to model arbitrary materials, but they are mostly designed to answer condensed-matter theory questions about solid-state (periodic) structures. The majority of the codes use an all-electron implementation of density-functional theory. This includes several forms (...

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