Questions tagged [defects]
For questions about modeling material defects (e.g. vacancies, interstitial/substitutional impurities, topological defects).
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Calculation of charge defect formation energy
I am confused about the calculation of the charge defect formation energy equation with these two terms (from figure below):
$\Delta V$: alignment term, and
$E_{corr}$: correlation term.
How can I ...
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0
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What is the procedure for calculating the formation energy of a doped material?
To calculate the formation energy of a material AB with 2 atoms, I created a 2x2x2 supercell, resulting in a total of 16 atoms. Then, I removed one atom of type A from the supercell. From the ...
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Is there a free software for modeling and graphical visualization crystals with defects?
At real situation, it can happen, that a crystal can have defects, for instance, some of them are point defects — Schottky, Frenkel defects, line defects — dislocations, planar defects — grain ...
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How to calculate the formation energy of a defect using the unit cell? [closed]
I want to dope CuI conventional unit cell using Quantum ESPRESSO.
In previous papers they used different formulas of defect formation energies,and they use supercell. So I'm confused.
What's the ...
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How to determine defect charge state degeneracies?
I am doing defect calculations using the SC-FERMI package. However, one of the inputs is the degeneracy of the charge states of each defect. I know degeneracy is the number of states with the same ...
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Which formalism is better suited to model a crystal with defects: Hartree–Fock, Kohn–Sham, or something else?
Let’s suppose that
(1) it’s required to calculate a crystal with certain parameters of a crystal lattice;
(2) this crystal has some defects (let it be Frenkel defects for simplicity);
(3) these ...
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4
votes
1
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Decide the position of oxygen vacancy via the configuration with the lowest energy?
I am trying to determine the position of oxygen vacancy in $\ce{TiO2}$, is it reasonable to decide it by choosing the configuration with the lowest energy?
It doesn't feel quite right to always choose ...
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How to distinguish between deformation mechanisms in creep experiment? [closed]
As I'm learning more about viscoelasticity and creep experiments, I'm trying to understand how to distinguish between the different deformation mechanisms.
In general, when a sample of viscoelastic ...
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Difference of high-frequency and static dielectric constants? [closed]
I found in an article [1] the following definition of FNV (Freysoldt, Neugebauer and Van de Walle) energy correction term for a charged defect in a cubic supercell:
$$E_{\text{corr}}=\frac{\alpha_Mq^2}...
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votes
1
answer
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Relax vs VC-Relax for interstitial incorporation energy
In order to model an interstitial trapped in a metal lattice, and the associated incorporation energy, which should be used - "relax" or "vc-relax"? I want to understand the ...
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How to start with structural defects in monolayer?
First of all, thank you for your help!
You are so helpful every time.
I would like to calculate the influence of the structural defects on the electronic structure in the HfS2 monolayer. With VESTA ...
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What are the tools available for point defects calculations? [closed]
It would be appreciated if you could explain one of the tools below (or another tool not listed), in the format used here (for example):
What software will allow me to combine two images?
What ...
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What are good resources to study crystallographic defects in different dimensional systems and their topological dimensionality?
I wonder if there are any books or resources that may address one or more of the following questions:
What kinds of defects are important for topology? Especially crystallographic defects.
How do ...
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What are some approaches to modeling charged point defects in materials?
From what I understand, one major issue in modeling charged point defects in materials is the existence of artificial interactions between charged defects and their periodic images. Even when using ...
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