Re: [QE-users] Constrained DFT with QE

Dear Giacomo, not that I know, beyond OS-CDFT. In here http://theossrv1.epfl.ch/Main/OxidationStates there is a handwaving description on how to implement these things by hand, but you need a projection on the manifold of interest, and for that currently the only projections afaik are on

Re: [QE-users] Optimal pw command line for large systems and only Gamma point

On 13/05/2024 17:26, Giuseppe Mattioli wrote:     occupations= 'smearing'     smearing= 'cold'     degauss= 0.05 ! I know it's quite large, but necessary to stabilize the SCF at this preliminary stage (no geometry step done yet)     mixing_beta= 0.4 If you want to stabilize the scf it is

Re: [QE-users] Inquiry on Hubbard U Values for monolayer vs bulk

Hi - you can find here an in-depth discussion: https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.8.014007 nicola On 30/04/2024 09:45, Zimmi Singh wrote: Dear Developers and Users, I am currently working on transition metal dichalcogenides and

Re: [QE-users] Effect of magnetic order on dynamic stability

I don't think you can draw a general conclusion - a 2D material (or a 3D one) for a given geometry will have one or a few or many or infinite energy minima/selfconsistent states, where the global minimum and the local minima can be non-magnetic, ferromagnetic, or antiferro or ferrimaginetic,

Re: [QE-users] sfc calculation for ROY structures

Hi Nikos, energies are relative, so nothing wrong in principle. But you cannot do anything meaningful if you do not study first materials simulations and electronic-structure methods, and try out some simple cases. A few pointers:

Re: [QE-users] fail in running Koopmans

Dear Zongyi Wang - this below from Edward Linscott: To resolve this issue, decrease the total number of nodes allocated to this job; 128 is excessive. (We plan to make the workflow deal more intelligently with cases such as these -- see e.g.

Re: [QE-users] Too few bands

On 22/03/2024 13:05, aleksandr.doma--- via users wrote: 1) Is it acceptable to use SSSP library of pseudopotentials: Materials Cloud Materials Cloud Materials Cloud is built to enable the seamless sharing and dissemination

Re: [QE-users] Phonon calculation does not converge

Out of curiosity, wouldn’t a low cutoff (not that one should use it) miss a ghost state (that is very localized)? In passing, sssp pseudos are tested re not having ghosts, and have default suggested cutoffs. Just make sure you use the latest version 1.3 Nicola Sent from a tiny keyboard...

Re: [QE-users] [SPAM] Convergence issue in spin-polarized SCAN calculation

Hi Michal, these are two different problems - lack of convergence is not driven by pseudopotentials, but by algorithms. CASTEP uses a variational minimization, that is bound to converge, but tends to be slower - QE is iterative. Changing pseudopotentials might randomly make your

Re: [QE-users] NMR of Metallic Systems

On 23/11/2023 12:03, Davide Ceresoli wrote: Dear Megan, the orbital shift is implemented, the Knight shift no. I can't get it to converge with respect to k-points. Best, Davide Spot on! We worked on this a long time ago - https://journals.aps.org/prb/abstract/10.1103/PhysRevB.76.165122 and I

Re: [QE-users] Stiffness Matrix

Sure - exercise 3 of this tutorial: Materials Cloud

Re: [QE-users] In Phonon Calculation for Raman Spectra, How to decide to use how many unit cells?

Dear all, I think there is a profound misunderstanding here - make sure you understand the difference between primitive-cell calculations and density-functional perturbation theory at any arbitrary q wavevector (read 2001 RMP by Baroni et al) and finite-difference calculations in a

Re: [QE-users] Born Huang and Huang invariance conditions

Thanks - thhis is the paper: https://www.nature.com/articles/s41524-022-00920-6 and in the matdyn (https://www.quantum-espresso.org/Doc/INPUT_MATDYN.html) this is the option 'all'. Not sure about q2r - should be there as well, but I do not see it - but maybe I'm missing something?

Re: [QE-users] can i use this trick to do faster MD calculation using pw.x ?

Hi Jayraj, you wrote several times, but probably many did not know where to start - because you are addressing several complex problems without seeming to have much background in the field. Answers to your 3 points: 1) you will not get anything meaningul with the low cutoffs you suggest,

Re: [QE-users] Spin counting in hp.x with paramagnetic metals

Dear Theo, unrelated, but it's not a super good idea to describe a paramagnetic state with a non magnetic calculation - many paramagnetic systems have still strong local moments, that are disordered. At high pressure the local moments can disappear (e.g. iron at the ~330GPa of the

Re: [QE-users] question about last steps of vc-relax

Thanks Paolo! This is a chance to remind everyone that there are sets of carefully tested pseudopotentials (PBE and PBEsol) with suggested cutoffs on https://materialscloud.org/sssp ; these cover the entire periodic table. There are two choices - efficiency or precision. They have been

Re: [QE-users] Fwd: Hydrogen atom pseudopotential files with q=1.5e and q=0.75e (PBE, USPP)

Dear Gökhan, as far as I know there is a legacy table of old pseudopotentials: http://pseudopotentials.quantum-espresso.org/legacy_tables/original-qe-pp-library It's not recommended in general, but for H you can find some old Von Barth Car pseudos with fractional charges (maybe good to

Re: [QE-users] Download old versions of QE

On 16/01/2023 15:26, Schubert Yannick via users wrote: Dear all, I am looking for QE version 4.1 but can not find it on the new QE homepage anymore. Is this code still accessible somewhere? Best, I have 4.0.5 and 4.3.2, but not 4.1 - happy to contribute those (would be great to have a

[QE-users] Two tenure-track positions on electronic-structure simulations (Paul Scherrer Institute, Laboratory for Materials Simulations)

Dear QE Community, this is to announce the opening of two tenure-track scientist positions in the Laboratory of Materials Simulations (https://www.psi.ch/en/lms) that I direct at the Paul Scherrer Institute. These will lead to permanent appointments after a successful evaluation within a

Re: [QE-users] phonon bands shift

It could well be correct - lo-to splitting in low symmetry systems leads to different limits at gamma depending on direction. Nicola Sent from a tiny keyboard... Contact info: http://theossrv1.epfl.ch/Main/Contact > On 17 Sep 2022, at 15:18, Aleksandra Oranskaia > wrote: > >  > Dear users

Re: [QE-users] gamma points calculation

For intermediate sizes I tend to use the Baldereschi point ¼ ¼ ¼ and nosym .true. - unhortodox, breaks symmetry, wfc are complex, but almost as accurate as 2 2 2 1 1 1 at ¼ of the cost. nicola Sent from a tiny keyboard... Contact info: http://theossrv1.epfl.ch/Main/Contact > On 15 Sep 2022,

Re: [QE-users] Molecular dynamics calculation crashing

Try the parameters from this, and report? https://www.materialscloud.org/work/tools/qeinputgenerator 130Ry seems excessive, and difficult to say without knowing the other parameters of the run Sent from a tiny keyboard... Contact info: http://theossrv1.epfl.ch/Main/Contact > On 7 Aug 2022,

Re: [QE-users] WFs confined within the unit-cell

On 01/08/2022 18:03, Nicola Marzari via users wrote: or between different unit cells. Apologies - I meant: --> or between different MLWFs in different unit cells. nicola -- Prof Nicola Marz

Re: [QE-users] WFs confined within the unit-cell

Dear Emanuel, a few pointers here: - in the calculations, you have a real space unit cell A (whatever it is; it can be the primitive one, or a larger one); its corresponding Brillouin Zone B is sampled with a k1xk2xk3 monkhorst-pack mesh, with k1/k2/k3 integers. In principle, k1/k2/k3 are

Re: [QE-users] Advanced Quantum ESPRESSO tutorial: Hubbard and Koopmans functionals from linear response

Very nice! If you haven't already posted to Psi-k, highligt keynote speakers early on On 29/07/2022 11:02, Iurii TIMROV via users wrote: Dear Quantum ESPRESSO community, We are pleased to announce the "Advanced Quantum ESPRESSO tutorial: Hubbard and Koopmans functionals from linear

Re: [QE-users] vdW not implemented for nspin > 1 in QE 6.5

Also, stress can always be verified by looking at the numerical derivative of an energy vs strain curve, making sure the cutoffs on wfc and rho are large enough so that the stress tensor is converged. Nicola Sent from a tiny keyboard... Contact info: http://theossrv1.epfl.ch/Main/Contact >

Re: [QE-users] Is it acceptable to neglect spin, magnetism and U for CPMD simulation of iron oxides (Fe2O3, Fe3O4 and FeO)

Thanks Giuseppe, couldn't agree more! Never being one to miss an opportunity to promote dft+hubbard, I would also add that these functional can be also more accurate, because they screen a fock-like term with awareness of the local bonding - see Iurii's just-out work on batteries:

Re: [QE-users] Slow convergence

Thanks Paolo! Max - you say you are using the pseudos from http://theossrv1.epfl.ch/Main/Pseudopotentials, but you are actually not. There is a sentence at the beginning of that page, in very large fonts, that that tells you what to use - and then there is a long list of other entries,

Re: [QE-users] Pseudopotentials for all-electron DFT calculations

Hopefully this one http://pseudopotentials.quantum-espresso.org/upf_files/H.coulomb-ae.UPF and you just change the z valence. By the time you get to carbon (zval 6) you are looking at 500-1000 Ry of ecutwfc Nicola Sent from a tiny keyboard... Contact info:

Re: [QE-users] banduppy for band unfolding

Dear Kenneth, there is a very comprehensive tool to obtain k-point paths that are compliant with the guidelines from the international union of crystallography - I strongly recommed you use those. You can find it online here: https://www.materialscloud.org/work/tools/seekpath with also

Re: [QE-users] Defining C diamond structure cp.x

Dear Juniper, if your long-term goal is to study warm dense matter, you want to do molecular dynamics simulations with CP or PW in a large supercell, and with no symmetry (ibrav=0). Of course, if you want to learn how to do calculations (it's a long and winding road) you could practive

Re: [QE-users] LDA normconserving pseudopoential Cu

Dear Johannes, There are a couple of standard ones to look at - both multiple-projectors norm conserving (ONCV) - not sure if the raman code in qe is compatible with them. One set is the Schlipf-Gygi: http://www.quantum-simulation.org/potentials/sg15_oncv/ that is tested e.g. by us:

Re: [QE-users] Enquiry about electron-phonon calculation

On 06/12/2021 08:59, Lorenzo Paulatto wrote: Yet it is possible. You need a very goo representation of the Fermi surface in order to identify the possible el-ph processes, but such a fine grid is not required to have good phonons. Also note that there are at least two QE packages to do el-ph

Re: [QE-users] Oscillating volume in VC-MD

Dear Andrii, maybe the small oscillations are not so important, depending on what you want to achieve. If you are really keen on investigating further, you could do a fairly short run using MD with fixed cell, and average the stress tensor over that run - 1/3 of the trace would tell you how

Re: [QE-users] Oscillating volume in VC-MD

Dear Andrii, this might be related to the fact that the more harmonic a system is, the more difficult it is to thermalize it - since it's anharmonicity that shuffles excitations. [If you have a system of harmonic oscillators, the populations are good quantum numbers, i.e. they are

Re: [QE-users] How to improve the values calculated using QE?

you are much more > handsome than Brad Pitt. SB > >> On 11 Nov 2021, at 19:21, Nicola Marzari via users >> mailto:users@lists.quantum-espresso.org> >> <mailto:users@lists.quantum-espresso.org <mailto:users@lists.quantum-espresso.org&g

Re: [QE-users] How to improve the values calculated using QE?

Blush :-) nicola On 11/11/2021 19:25, Stefano Baroni wrote: Actually, at a closer look, and under any lighting, you are much more handsome than Brad Pitt. SB On 11 Nov 2021, at 19:21, Nicola Marzari via users <mailto:users@lists.quantum-espresso.org>&

Re: [QE-users] How to improve the values calculated using QE?

Dear Tarik, DFT is not a theory that describes electronic excitations - there is only the total charge density in DFT, and it describes the ground state. If you use Kohn-Sham DFT to approximate the kinetic energy functional introducing the non-interacting Kohn-Sham particles, these lead

Re: [QE-users] [QE-developers] Inquiry: Quantum Espresso

Dear Galina, ENVIRON (http://www.quantum-environ.org) is a fairly comprehensive approach for Quantum ESPRESSO simulations in the presence of an implicit solvent and an electrolyte. nicola On 08/11/2021 18:53, Galina Galina wrote: Dear Quantum Espresso,

[QE-users] Two posdoctoral openings - Wannier/Hubbard/Koopmans

Dear QE forum, in case someone is interested, we have two openings for postdoctoral positions in code/method development, for Wannier-based Hubbard and Koopmans functionals to run on accelerated architectures - so very suited for people with a methodological and parallel/C++ coding slant.

Re: [QE-users] Atomic velocities units

On 10/08/2021 11:39, Lorenzo Paulatto wrote: The velocities are both printed in any place, but it is not the first time I get this request, maybe it could be added in the future. That said, they are trivial to compute v(t)=(r(t-1)-r(t))/dt -- Lorenzo Paulatto quick one - maybe better as

[QE-users] review on electronic-structure methods and computational materials design

Dear QE users, with Andrea Ferretti and Chris Wolverton we have written a review for Nature Materials on electronic-structure methods that is out today: https://www.nature.com/articles/s41563-021-01013-3 We are also allowed to distribute an open access, view-only version:

Re: [QE-users] under pressure PbTaSe2 vc-relax calculation

Dear all, 1) a perennial recommendation of mine is indeed to make sure the cutoffs for wfcs and rho are both enough to have the stress well converged - this was one key critiations for the SSSP (that you can find here https://www.materialscloud.org/discover/sssp/). Reasonably tuned

Re: [QE-users] Query about density of states calculations for crystalline and amorphous supercells

Mostly yes - e.g. look at the work of Pasquarello's group (and many others, of course) on the topic - many menaningful papers in the past 20 years. nicola On 20/05/2021 18:41, alex davila wrote: Dear all, I am interested in learning if QE is suitable for DOS

[QE-users] postdoctoral (or PhD) positions on spectroscopies with Quantum ESPRESSO and ENVIRON

Dear Quantum ESPRESSO users, in case some of you are interested, we have two postdoctoral openings in the group, to develop first-principles spectroscopies using Quantum ESPRESSO and the electrochemical libraries of ENVIRON. All details at