Questions tagged [quantum-espresso]

Questions related to the open source materials modeling framework, Quantum Espresso.

Filter by
Sorted by
Tagged with
5
votes
0answers
27 views

Is it possible to install thermo_pw on windows 10?

For research purpose, my team needs to use thermo_pw package for ab-initio simulations. But the issue we are running into is that we cannot find a way to install it on our computer. We are using ...
6
votes
0answers
39 views

Why does the Fermi energy change when doing NSCF at different nbnd values?

While doing NSCF, I decided to rerun it at higher nbnd values to incorporated more unoccupied states while plotting PDOS. But the Fermi energy gets changed with ...
11
votes
2answers
324 views

What is the difference between DOS and PDOS?

I'm new to DFT. Can you please help me to understand DOS and PDOS (projected density of states) in simple wording? I only want to know some basics of these terms and how they are linked to DFT.
7
votes
1answer
36 views

How to determine the more stable configuration between a flat and a buckled monolayer with DFT?

Using first principles methods (quantum espresso code) I would like to find if a monolayer of a material is flat or buckled. Using the van der Waals interaction in the calculation I found that the ...
8
votes
2answers
308 views

Pressure applied DFT calculations in Quantum ESPRESSO

I am trying to perform the pressure-induced DFT calculations in Quantum ESPRESSO. For this, I have calculated the lattice constant of the cubic structure by vc-relax...
9
votes
1answer
52 views

Are electron dipolar spin-spin interactions included in DFT calculations?

I am studying point defects in hBN using Quantum ESPRESSO. It is not clear if electron spin-spin interactions are typically/can be included in DFT calculations. I understand that spin-orbit ...
6
votes
1answer
39 views

Vibrational frequency analysis for NEB result through Maestro

I have ran a Nudged Elastic Band (NEB) calculation using QuantumEspresso through Maestro to find the potential transition state. Within Maestro there is an option where you can select for NEB type ...
6
votes
0answers
68 views

Is there a software package to analyse interactions in crystals?

I have been using Quantum ESPRESSO, specifically the pp.x module to study interactions via charge density plots. The process is slow as for crystals containing ...
7
votes
0answers
25 views

How do I get exact percentage of spin-polarization in Quantum ESPRESSO?

I am investigating a near half-metallic / high-spin polarization material. I ran an SCF calculation with nspin = 2, with some starting magnetization. So now I ...
7
votes
0answers
63 views

How to fix gauge in Quantum Espresso?

I am trying to use Quantum Espresso to manually calculate the Berry phase using the Berry connection, due to evolution along a closed loop in k-space. I want to do this manually instead of using ...
10
votes
1answer
67 views

Can I do a “constrained” geometry optimization in Quantum ESPRESSO, such that certain dopants appear in certain positions even after relaxation?

I am studying the magnetic properties of bulk ZnO, so I am doping it with transition metal elements in order to observe the magnetic spectrum. I replace a Zn atom with a transition metal element at ...
4
votes
1answer
54 views

How can I obtain seperate spin-up and spin-down bands while considering Spin Orbit Coupling in Quantum ESPRESSO?

I have been studying a magnetic material with SoC taken into consideration. The main aim was to obtain the band structure. when I use spin_component = 1 in the ...
7
votes
1answer
97 views

How to understand the wavefunction outputed by QE with HDF5 format?

Following the answer to my question: What is the best program to manipulate numerical DFT wavefunctions to calculate custom matrix elements?, I compiled Quantum ESPRESSO with the hdf5 flag on, and now ...
9
votes
2answers
97 views

Can we consider SOC in FM materials using QE?

This is a follow-up question to my question posted here. I've been trying to study the effects of spin-orbit coupling (SOC) on the band structure of ferromagnetic (FM) material VSe$_{2}$. The input ...
11
votes
1answer
44 views

How can I properly attach ligands to a surface?

The main aim of my venture is to study the effect of the presence of surface ions on the band structure of Si slab using Quantum ESPRESSO. I've tried to use iQmol to attach ligands to the surface. The ...
10
votes
1answer
240 views

How to make sure that my SCF calculation is correct?

hope you are doing well. I am trying to study the electronic properties of ZnO doped with transition metals (Co, Ni, Fe) using DFT calculation, I am a beginner on DFT calculation using quantum ...
5
votes
0answers
79 views

How to use hp.x in Quantum ESPRESSO to calculate Hubbard parameter

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 ...
8
votes
0answers
62 views

Band structure has unusual lines in the valence band using Quantum ESPRESSO

Currently, I am working on ZnO doped with nickel and cobalt. I performed the SCF, NCF, BANDS calculation and got the results, the calculation converges without any errors. After that I used BANDS.X to ...
12
votes
1answer
99 views

What is the best program to manipulate numerical DFT wavefunctions to calculate custom matrix elements?

For pedagogical reasons, I am looking for ways to calculate quantum-mechanical quantities such as $\langle m | \dot{m}\rangle, \langle m | \dot{n}\rangle, \langle m | \ddot{n}\rangle$ using ...
9
votes
1answer
101 views

Should I use a lower threshold for calculations involving SOC?

I'm studying a compound $\ce{VSe_2}$ using the DFT package Quantum ESPRESSO (QE). The following is the input file. ...
4
votes
0answers
28 views

Is there a way I could calculate the pressure and use SOC at the same time?

I have been trying to find the appropriate k-point grid via convergence in quantum ESPRESSO (QE). The following is my input file. ...
6
votes
1answer
46 views

Understanding QuantumEspresso Toolbox through Maestro

Anyone here uses Quantum Espresso through Maestro can tell me a bit more about the calculation panel setting: I understand that -npools option must be divisible by ...
6
votes
1answer
66 views

How can I properly represent paramagnetic materials in DFT calculations?

I have seen specific ways of constructing input files for Anti-ferromagnetic materials Ferromagnetic materials. How can I represent a paramagnetic material in plane wave DFT codes like Quantum ...
5
votes
0answers
37 views

At what threshold would I assure convergence?

I'm a beginner in DFT and Im using quantum espreso. I've seen the difference of hydrostatic pressure being used as a criteria for converging my k-point grid and plane-wave cut-off values. I would like ...
5
votes
0answers
27 views

Recommended code to do XAS/XES/RIXS calculations with?

I am a grad student looking to simulate several XAS/XES and potentially RIXS spectra for some strongly correlated metal-oxides. The materials in question will likely require solving the Bethe-Salpeter ...
7
votes
3answers
335 views

For which elements should I include spin orbit coupling in Quantum ESPRESSO?

I'm trying to study a Yb-Ge-Sb compound and would like to include spin-orbit coupling (SOC). In Quantum ESPRESSO, this is done by including the following tags in the ...
9
votes
1answer
348 views

How can I know if 3D aperiodic systems are not interacting with each other using Quantum ESPRESSO?

I wanted to observe the Projected Density of States of InP system passivated with Hydride ions. For that, the following input file was created. ...
5
votes
0answers
44 views

Is it necessary to terminate the surface ions in a quantum dot?

I was trying to study quantum dots of ZnO. But I'm pretty new to creating and passivating 0 D particles. Is it always necessary to passivate the free surface of the quantum dot? Regarding the studies ...
10
votes
2answers
244 views

How to perform charge analysis for a molecule

I am doing dehydrogenation of a molecule (say $\ce{C12H12}$) and I want to do charge analysis for dehydrogenated system ($\ce{C6H6}$). How I can proceed? I can use Quantum ESPRESSO and Gaussian ...
8
votes
2answers
146 views

inconsistent behavior between band structure and density of states

I'm a beginner in DFT calculation. I have performed a DFT calculation on CuCoSnSe using PBE-GGA on Quantum Esspresso. When I plot the band structure and the total DOS, the band structure shows a ...
4
votes
0answers
39 views

Incosistent charges and magnetic moments between SCF and PDOS calculations in Quantum Espresso

I have a system of 5 layers of an element + 1 layer of another one, I want the relaxed position of the last layer, and once I have it, proceed to calculate the pdos. I am performing simulations in the ...
7
votes
1answer
107 views

Smearing and charge balance for tungsten with interstitial oxygen in Quantum ESPRESSO

What smearing would be ideal for a bcc W with interstitial O atom. I am running 3x3x3 unit cells with one N interstitial. I am having convergence issues in relax ...
12
votes
2answers
257 views

Getting different total magnetic moment in 'scf' and 'vc-relax' calculations in Quantum ESPRESSO

I am performing a spin polarized DFT calculations in Quantum Espresso on a Co2MnSi ferromagnetic crystal. For this I have performed these steps: 1) Performed ...
18
votes
4answers
848 views

Is it possible to calculate the Curie temperature for magnetic systems?

Using DFT calculations we can know the electronic and magnetic property of the system at 0 K. I am wondering if there is any computational method to know the curie temperature of magnetic materials? ...
9
votes
1answer
116 views

Is the “Final Magnetic moment” in the materials project repository same as the “total magnetization” value in Quantum ESPRESSO output files?

I'm quite new to spin-polarized DFT and have been trying to study $BaVSe_{3}$ which is ferromagnetic (with a Final Magnetic Moment of 0.052 Bohr Mag) as per the Materials Project repository [picture 1]...
10
votes
1answer
123 views

How to analyze the band symmetry with Quantum ESPRESSO?

This question is related to this paper: J. Phys. Chem. Lett. 2017, 8, 13, 2999–3007 The above figure shows symmetry analysis for the band structure. The author writes: The band symmetry and parity ...
7
votes
1answer
45 views

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 ...
5
votes
1answer
92 views

Is there a difference in performance when the symmetry is specified via ibrav in Quantum ESPRESSO?

I have been using cif2cell for converting CIF files into quantum ESPRESSO input files. But cif2cell always keeps the ibrav value to be zero and indicates the CELL_PARAMETERS. As per the quantum ...
13
votes
2answers
165 views

Deciding the number of CPUs for a DFT calculation for band structure in Quantum ESPRESSO?

If I am using Quantum ESPRESSO for bandstructure calculations, how can I know the number of CPUs necessary for such a calculation? I deal mostly with ternary transition metal oxides which have at ...
10
votes
1answer
112 views

How many GB of RAM would be needed for VASP to evaluate optical properties of a material?

Even though it is a powerful tool, Quantum ESPRESSO's hardware requirements are very high. For instance, to evaluate optical properties, even for structures with tens of atoms, Quantum ESPRESSO can ...
6
votes
1answer
265 views

How to choose starting magnetization while doing spin polarised calculation in Quantum ESPRESSO?

I am trying to run spin polarised DFT calculation in Quantum ESPRESSO on system Co2MnSi. I kept starting magnetization for all these three species as, ...
10
votes
1answer
215 views

How to calculate the energy of conduction band and valence band with respect to vacuum in quantum espresso?

I was able to calculate band energies in quantum espresso. How to convert them to values that are in terms of difference from vacuum energy?
9
votes
1answer
70 views

Can you list some useful code snippets for processing quantum ESPRESSO output files?

I know that this is quite general. But we have all written code for processing output files from various dft codes. The functionality of which, may range from analysing time traces to finding ...
8
votes
1answer
164 views

Spin polarized DFT calculation in Quantum ESPRESSO

I am trying to run spin polarized DFT calculation on system Ti2FeSn. I am doing vc-relax calculation to relax the unit cell but having problem to converge total energy. Total magnetization is also ...
14
votes
2answers
1k views

What is nscf calculation in Quantum ESPRESSO?

I have been using 'nscf' for DOS calculation since it is faster and therefore possible to use a higher kpoints. But why is it faster? why not use it in the place of 'scf'?
8
votes
1answer
138 views

How to model electric field in Quantum ESPRESSO?

I have seen papers that take change in Gibbs Energy by just adding a 'eU' term where U is the potential applied. Is there any better way to do this in Quantum Espresso? And is the former way accurate ...
9
votes
1answer
182 views

How to apply solvent model in Quantum ESPRESSO?

In many cases especially when it comes catalysis (which is what I work in) the effect of solvent comes into effect. I have seen papers that takes into account water as solvent by adding a number of ...
5
votes
1answer
61 views

How to separate the band structure of different materials in heterostructures using Quantum ESPRESSO?

So, I know that to calculate surface band structure of a material, you have to take its 2D system eg. single or few-layered. But, how to find the surface band structure in the case of heterostructures....
10
votes
2answers
483 views

Plotting density of states of Fe(BCC) using Quantum ESPRESSO

I have run the DFT calculation and plotted DOS of Fe(BCC) in Quantum ESPRESSO. I have attached the plot: (click on image to see clearly) But It's a wrong plot as it is not matched with the referenced ...
8
votes
1answer
131 views

How to extract the Pressure, Energy and unit-cell volume from quantum ESPRESSO output file using bash script?

I needed the Energy and Volume values for predicting the bulk modulus of a crystal via the Birch Murmaghan equation. Can I get a bash script for doing the same.