Questions tagged [pseudopotentials]
Refers to the approximation of core electrons by effective potentials. Used in plane-wave and Gaussian based theories.
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Which approach should one follow if a pseudopotential underestimate/overestimate some electronic properties from experimental value?
I have seen during DFT calculation some authors comment that LDA/GGA functional overestimates/underestimates the band gap/lattice constant of some materials. Before going to the main calculation, it ...
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Pseudo potential generation for XPS calculation
I want to compute the XPS spectrum for an iron oxide using pseudo potentials, and I would need some guidance in how to generate the necessary pseudo potentials. I am using a great software called APE ...
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Is there a repository for PSML pseudopotentials files?
I am looking for repositories with tested pseudopotentials in PSML format to be used with SIESTA software.
At least in my notebook, the Pseudo-Dojo that claim to support pseudopotentials for different ...
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Identifying non-relativistic, scalar relativsitic and full relativistic POTCAR
How to identify if the given VASP POTCAR pseudopotential is non-relativistic, scalar relativistic or fully relativistic from the content of the file? For example, I found EATOM values in relativistic ...
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oncvpsp code usage for pseudo potential generation
Here is the link to the code: oncvpsp
I am trying to modify the LDA norm conserving pp for Ruthenium (an element I have come to despise!). All the newer pp files for it are generated with valence 16 ...
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Why are some pseudopotentials not readable in Quantum Espresso?
I am using the pseudopotentials generated using "atomic" code by A. Dal Corso after downloading the pslibrary.0.3.1. ...
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How to choose hybrid pseudopotentials in Quantum ESPRESSO?
I am trying to perform DFT calculations on lead halide perovskite system using Quantum Espresso However, I am confused in choosing the pseudopotentials. The hybrid pseudopotentials are recommended to ...
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vc-relax calculation not converging with some pseudopotentials
I am new to Quantum ESPRESSO and it's my first calculations with $\mathrm{CsPbBr}_3$ perovskite structure. I am trying to perform vc-relax calculations. The ...
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Is there an Optimized Norm-Conserving Vanderbilt (ONCV) pseudopotential of Eu atom?
I'm currently searching for an Optimized Norm-Conserving Vanderbilt (ONCV) pseudopotential of Eu, which has a localized f-orbital. But no matter how much I search online, I can't find it.
There is an ...
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knowing if the pseudopotential in the first step is correct via Haman procedure
Context and objective
This post is a follow up from here. I want to generate a pseudopotential for a Carbon atom. So I want to pseudize the 1s electrons.
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So $V^{\textrm{PS}}_{1l} = (1-f(r/r_{...
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Norm conserving pseudopotential procedure
There is this paper: Norm-Conserving Pseudopotentials mentioning a procedure to make a pseudopotential. There are many points that I did not get. Let's suppose we already have the results from the all-...
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Find the outermost peak of a function to calculate the cutoff radius for pseudopotential calculation
Problem presentation
The problem mentioned in this paper about norm conserving potentials. I cite ...
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Treatment of f-electrons in SIESTA
Please suggest me, how to treat pseudopotential and basis for f block elements like Sm in simulating Sm2O3.
I used the psml pseudopotential from pseudo-dojo database, which gives quite accurate ...
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How to save pseudopotential?
I aim to do a plane-wave calculation after computing pseudopotentials. There are many ways to build pseudopotentials and each of them have their set of parameters.
What is the relevant piece of ...
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Generating a pseudopotential for graphene: Is it done on an individual carbon atom, or on an entire unit cell of graphene?
Let's take the example of a 2D graphene layer. The objective is to do an electronic calculation with only the valence electrons with a plane wave basis. Hence the need to pseudize the core electrons ...
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What is the Herman-Skillman method?
In the paper Norm-Conserving Pseudopotentials (1979), they refer to the authors' book for the all-electron(AE) calculation:
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Where can I find BLYP pseudopotentials?
Quantum ESPRESSO doesn't support pseudopotentials for hybrid functional. Instead they suggest using pseudopotentials for the non-hybrid functional that is closer to the hybrid one, i.e., PBE for PBE0 ...
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Is there a way to add 4f-oribital information in Pseudopotential?
Now, I'm calculating with a Quantum Espresso program
I want to need Eu pseudopotential file with 4f orbital information. But I couldn't find that file, no matter how much I search on the internet. ...
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How to read UPF pseudopotential for ultrasoft pseudopotential simple in a fortran program
I'm currently working on calculating semiempirical local and nonlocal matrix elements for Ga. To proceed with my calculations, I need to extract specific parameters from the UPF (Unified ...
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Why am I getting a wrong lattice constant from these SIESTA calculations?
I am currently learning to perform calculations on solids and am attempting to manually optimize the size of a face-centered cubic (FCC) cell of Nickel (Ni) using SIESTA (v. 4.1.5) with the Perdew-...
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How to estimate the minimal distance between atoms for which a pseudopotential-based AIMD gets forces correctly?
I am doing ab initio molecular dynamics in VASP. As far as I know, pseudopotentials approximate all-electron potential far from the nucleus, and deviate from it near the nucleus.
When some of my atoms ...
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Types of pseudopotential for calculating optical properties? [closed]
What types of pseudopotential should I use for calculating optical properties in Quantum ESPRESSO?
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What does the "atomic pseudo charge-density" in the POTCAR file stand for?
Basically I am trying to find the initial guess of an atomic charge density [rho(r)] v/s the radial distance r.
Specifically I checked the "atomic pseudo charge-density" tag in the POTCAR ...
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What is the difference, if any, between an effective core potential (ECP) and a pseudopotential?
I've used these terms interchangeably for a while, but have noticed that in PySCF they are separate attributes.
Are there any crucial differences between an effective core potential (ECP) and a ...
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Norm conserving LDA fully relativistic pseudopotential in quantum espresso
For my calculation, I need fully relativistic LDA Norm conserving pseudopotential. I have searched for this in the existing library like PseudoDojo, SSSP, SG15, PSLibrary etc., but failed. However, I ...
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where to find the norm-conserving pseudopotential of rare earth metals?
I am trying to find the norm-conserving(NC) pseudopotential of rare earth metals, but all I could find are about Ultrasoft or PAW types. Is there any recommendation for NC type?
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What are the appropriate lattice constant , pseudopotential and atomic positions for BCC Na with 0 kbar pressure? (for Quantum ESPRESSO) [closed]
BCC Na is the most stable structure of Na, and the most stable structure gives the pressure around 0 kbar.
But a paper named "Structure stability in the simple element sodium under pressure" ...
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Could you please share a step by step to generate semicore pseudopotential? (for QUANTUM ESPRESSO)
could you please share a handy way (some concise and explicit step by step procedures) to generate semicore pseudopotentials - for novice learners?
This question, how to generate semicore ...
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Effective core potential (ECP) calculations
I'm setting up a simple Hartree-Fock problem in pyscf with ECPs to test things out. However, the numbers I get do not make sense to me as the energies are very different. I have never used ECPs before ...
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Mixing pseudopotentials with gaussian and plane wave basis
I am somewhat of a novice in computational chemistry of materials, and have been tasked to replicate simulations from a relevant paper. The paper is a bit scant on details so I am trying to recreate ...
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Need help about how I can get/generate semicore pseudopotentials to be used in Quantum Espresso DFT?
I would like to know if I can get/generate semicore pseudopotentials (some core electrons are also considered along with valence electrons) to be used in Quantum Espresso DFT. Actually, it would be ...
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Can energies obtained with different pseudopotentials be compared?
I calculated energies per atom of bulk configurations of transition metals in VASP in order to use them as reference energies for adsorption on surfaces, etc. I downloaded POSCAR files from the ...
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Any software that could convert the format of pseudopotential files? [closed]
I am using SIESTA 3.2, which seems to only support the .psf pseudopotential format, is there any tools that allow me to convert the pseudopotential files into another format? Or when generating the ...
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Scalar relativistic Calculation for pseudopotential
I am new to solid state calculation. I have a question about the pseudopotential in terms of the relativistic effect. In solid-state calculations, ultrasoft pseudopotential using PBE functionals are ...
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Understanding Illustration for Pseudopotential
I am new to solid state calculation. When I was reading about the pseudopotential documents, I always ran into a diagram that shows how pseudopotential will help to smooth the all-electron ...
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Quantum Espresso calculation for Deuterium
I am a new user of Quantum Espresso. I have to use Deuterium instead of Hydrogen for my work in DFT studies. Hydrogen Pseudopotential file is available in QE website. Please clarify what parameters I ...
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Citing a pseudopotential
I conduct my DFT calculations using the SIESTA DFT package. For this, I obtained the pseudopotentials from this site which says that they have obtained the data from the Abinit database. However I do ...
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Which specific perturbation do we consider applying to the potential when defining the energy derivative of the log derivative?
Norm-conserving pseudopotentials are defined such that the energy derivative of the log derivative of the real and pseudo wavefunctions agree at $r>r_c$. I understand that although valence ...
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How to understand the energy derivative of the logarithmic derivative of a wavefunction when deriving norm-conserving pseudopotentials
The 4th desirable property of a norm-conserving pseudopotential given by Hamann et al is for the 'logarithmic derivatives of the real and pseudo wave function and their first energy derivatives agree ...
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Quantum Espresso energy cutoff for different pseudopotential
I've been told that I should use the potentials from the Standard Solid-State Pseudopotential (SSSP) library in my simulations. I am interested in $\ce{Pt}$, $\ce{O}$, and $\ce{H}$. Oxygen is ...
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Error in nscf calculation while considering Spin Orbit Coupling in Quantum ESPRESSO
I am trying to do the band structure calculation considering the Spin Orbit Coupling but getting the following error:
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VASP GW PAW Pseudopotentials
What is the difference between the GW and non-GW potentials in VASP. While it is clear that the GW potentials should be used with GW calculations, the documentation also states that these potentials ...
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Recommendations to treat 4f electrons (valence) of Yb3+ in magnetic systems in VASP
I need help with: I would like to know what is the most common approach to treat valence 4f electrons of lanthanides (3+ charge) in VASP that circumvents the calculation problems shown below. (or more ...
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What does the "pn" column mean in this pseudopotential file?
In this SSSP pseudopotential file for Quantum ESPRESSO, what does the "pn" column mean?
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What is a Padé approximant?
I have been looking at using Goedecker-Teter-Hutter (GTH) pseudo-potentials and I came across the abbreviation PADE.
I was wondering what this abbreviation actually stood for and how it is related to ...
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Convert PSP8 pseudopotential files to UPF format
Is there a way to convert psp8 pseudopotential files (used for abinit) to UPF format (used for Quantum ESPRESSO)? I noticed there is the upfconv.x utility in ...
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Linearized Augmented Plane Wave Method vs. Pseudopotential Methods
While reviewing some DFT literature, I have come across a few papers utilizing the LAPW (Linearized
Augmented Plane Wave) method, but I am interested in understanding why exactly one would use these ...
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What are some of the advantages and disadvantages when using shape consistent pseudopotentials as compared to energy consistent pseduopotentials
From the literature as well as the answer to the question What is the meaning of energy-consistent and shape-consistent in the context of pseudopotentials? I can see that the key difference between ...
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Why are Norm-conserving Pseudopotentials considered so important?
So I am aware that a norm-conserving pseudopotential enforces the conditions that:
Inside the cut-off radius, the norm of each pseudo-wavefunction is identical to its corresponding all-electron ...
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What is the meaning of energy-consistent and shape-consistent in the context of pseudopotentials?
I am trying to use pseudopotentials to model scattering from heavy molecules.
However, I am confused by some of the terminologies of pseudopotentials/ECPs:
Norm-conserving according to Wikipedia and ...
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