Questions tagged [dft-u]
Questions related to DFT+U, where U is an extra term involving the Hubbard potential.
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Phonon Dispersion of SrTiO3, EuTiO3 using Quantum Espresso (DFT-U)
the last few days I've tried to calculate the phonon-dispersion of SrTiO3 (STO) and EuTiO3 (ETO) using the PHonon package of QE. SCF, DOS, PDOS and Bandsctructure calculation worked well on these ...
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DFT+U for RPA Ground State
For RPA calculations in VASP, a four step process can be utilized where the first step is to compute the occupied orbitals at either the GGA or hybrid GGA level.
I am curious with materials that are ...
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Do the U values affect structure optimization with the DFT+U simulation to optimize crystal structure?
I am trying to do structure optimization of TiO2, since titanium is a transition metal, I need to use DFT+U to simulate the right band structure, but the electronic band structure would also affect ...
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In which conditions can the self-consistent Hubbard U value calculated using Quantum Espresso be used for other VASP calculations?
I have seen that some articles calculate Hubbard $U$ value self-consistently using Quantum Espresso code. Then, they use it in VASP calculations. My question is: In which conditions can this value be ...
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How to perform linear response theory calculation of U Hubbard parameter in VASP?
Following to this post, I would like to know how to perform linear response theory for calculation of U Hubbard parameter in VASP?
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How to create a CIF using VESTA? [closed]
I am looking into double perovskite materials. One of the possible materials is $\ce{Cs4CuSb2Cl12}$. Now, although there are a few papers which have done ab intio calculations but none of the common ...
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How to calculate formation energy using DFT+U?
I noticed that a lot of articles use DFT+U methods to calculate different formation energies when using regular DFT and DFT+U methods. For example, in the attached paper[1] on $\ce{In2O3}$, the ...
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How To calculate formation energy of Ni doped ZnO system in Quantum ESPRESSO?
I have successfully completed the SCF of doped system Ni doped ZnO using GGA+U. I have checked the SCF.out file and found the energy value : E= -6112.0389 Ry.
Hwo to calculate the formation energy of ...
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Handling multiple self-consistent solutions with DFT+U
It is well-established that within the DFT+U framework, one can achieve several self-consistent solutions with greatly varying energies for the same exact magnetic ordering. In 2010, Meredig et al. ...
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Will there be a difference between GGA and GGA+$U$ for material with Sc element involved?
I have a material that contains the transition metal element Sc [3$d$1], and I want to know your opinions if there will be a difference between GGA and GGA+$U$ calculation. Knowing that the other ...
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How to determine the value of the difference (U-J) in "Dudarev's approach" for GGA+U calculation using the VASP?
I want to conduct GGA+U calculations using Duradev's approach in VASP code on a ...
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How to use hp.x in Quantum ESPRESSO to calculate Hubbard parameter [closed]
I want to work with GGA +U on Quantum espresso to calculate the electronic properties of Ni Co co-doped ZnO system, but I can't figure out how to use the hp.x program for my system to calculate the ...
13
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Hubbard U correction for Copper
I am reviewing some information in the Materials Project and notice that they do not use DFT+U to model copper oxides. Since the methodology for fitting U is largely based on the 2006 Ceder paper, I ...
11
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Charge density convergence within VASP using spin polarized DFT+U
I am noticing a possible convergence problem in a magnetic $U$ system I am studying. In the OSZICAR file I often see the rms(c) value go to about ...
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Are there any good books to learn how to use DFT+U?
I am interested in learning how to do DFT+U calculations and was wondering if anyone has any good recommendations for books or articles.
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Determine DFT+U values by linear response
I am currently trying to determine how DFT+U values can be determined self consistently. I see that the bare and converged linear response matrix contain the difference in occupancies from the ground ...
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Apply DFT+U to Oxygen/Nitrogen p Orbitals
I often see DFT+U corrections for transition metals with delocalization problems, but a comment about applying a U correction to nitrogen or oxygen's p orbitals also shows up when digging around in ...
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DFT+U Values from Reference Formation Energies
I would like to calculate some DFT+U values for a few elements (Fe, Co, Ni, Cu, Zn?) and am attempting to take the approach from the Ceder 2006 paper. Where does the Ceder paper take its experimental ...
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Database or repository with values for the Hubbard potential U?
The Materials Project and other materials databases have a nice periodic table on their home page that allows you to search for compounds. For some materials, they give an empirical $U$ value used to ...