[Pw_forum] cp.x and the autocorrelation function of dipoles

Dear all I am currently trying to calculate the IR spectrum by taking the FFT of the Autocorrelation function obtained from a CPMD run in cp.x (QE 6.1). I recently stumbled across a post by Giuseppe Mattioli (http://qe-forge.org/pipermail/pw_forum/2015-July/107471.html) indicating that apply

[Pw_forum] QE 6.1 and HSE: change algorithm from ACE

Dear all! I am trying to use HSE to correct the band-gap (YAMBO has turned out quite memory heavy for this system) and I am running in some problems on QE 6.1 on the cluste (but not older version QE 5.x on my local machine) which seems to be related to the new ACE algorithm for handling the e

Re: [Pw_forum] how to calculation absorpation light in the quantum espresso

For optics, quasiparticle properties, … I can only highly recommend Yambo (www.yambo-code.org); I worked on several perovskite materials and it gives excellent results with reasonable calculation effort (hours~days). An excellent place to look for information is: htt

[Pw_forum] decomposition of dispersive forces by atoms

Dear all! Is it possible to separate forces on an atom-to-atom basis (A-B, A-C, B-C, in a compound with atomic species A,B,C, for example)? Grimme-D2 seems to describe a H-bonding phenomena quite well (judging from the orientation of H---Br) but being able to actually read the force (from tprnf

[Pw_forum] band-structure calculations in slab-vacuum geometry: how to find the "surface k-path"?

Dear all! I have come across an impasse and I am hoping for some stimulating input… I work on CsPbBr3 (cubic unit cell, a=5.6 A). I construct a vacuum (5L)-slab (7L)-vacuum (5L) (L=layer numbers in multiple of the lattice constant in z-direction) symmetric slab (exposing the 100 CsBr terminat

Re: [Pw_forum] intrinsic dipole of (large, anisotropic) molecule

Dear Marton! Thank you for your very helpful reply with respect to the Makov-Payne correction and convergence with cell size. I was able to calculate a wide range of dipole moments for simple molecules (Water, formaldehyde, chlorobenzene...) with excellent agreement (~1-2% deviation to literatu

[Pw_forum] how to study adsorption geometry vs. energy? NEB?

Dear all! I am currently trying to study the absorption geometry of a molecule (chlorobenzene, pyridine) on metal surfaces (nothing new here…) using QE. I wonder if anyone could point me toward a worked example of some sorts how this can be done using either cp.x or neb.x. I am particularly cur

[Pw_forum] upcoming workshops, summer schools and how to find them?

Dear all! I apologize for this slightly off-topic question. I was wondering if anyone is aware of upcoming workshops or summer schools in the Asian region? I have seen that the QE homepage lists pasts workshops with links to the materials but I was unable to find upcoming workshops. My self-tea

[Pw_forum] method to create high-symmetry k-paths?

Dear all! Sometimes I have to plot the phonon dispersion along a certain k-path (G->X->R…). Usually I pick the k-path in xcrysden, then run a band structure calculation with crystal_b, pick the k-path from the out-file and insert it into my matdyn in file. But that procedure, despite working w

[Pw_forum] rebuilding ONCV PPs with PP_PSWFC for projwfc.x

Dear all! I have recently started using Harmann’s SG15 optimized norm-conserving PPs (http://www.quantum-simulation.org/potentials/sg15_oncv/). They give very nice “out of the box” band structures and lattice constants whilst using small cutoffs. I have to use a NC PP because of further process

Re: [Pw_forum] Convergence or band-gap problem in orthorhombic CsPbBr3

Dear Prasenjit! Thank you for your suggestion, this paper was, actually, my starting point. You have used US PP but for YAMBO I have to use normcons, otherwise my approach (vdW, …) was heavily “inspired” by your suggested paper. I find it highly interesting that the gap sometimes opens at Gamma

Re: [Pw_forum] Convergence or band-gap problem in orthorhombic CsPbBr3

Dear Frederico! The experimental band gap is 2.3-2.4 depending on the method used; my band gap is less than 0.5 eV - rather drastic underestimation. For the orthorhombic phase there are two or three references, but they do not agree well in terms of the location of the gap (sometimes gamma, som

[Pw_forum] Convergence or band-gap problem in orthorhombic CsPbBr3

Dear all! I am currently trying to simulate the electronic properties of CsPbBr3 in its low-temperature phase (orthorhombic; a=8.244, b=11.735, c=8.198 angstrom, according to Stoumpos; Cryst. Growth Des. 2013); My principle plan is to follow Radi et al. (arXiv:1405.1706v2), who have done this u

[Pw_forum] efficient parallelization of phonon jobs without manual distribution (GRID)

Dear All! I am currently looking into phonon calculations and I am a bit confused by the available methods of parallelization and their applicability to my system. I read chapter 5 (Parallelism) http://www.quantum-espresso.org/wp-content/uploads/Doc/ph_user_guide/node10.html and I briefly chec

[Pw_forum] make ph strangely stops without error in 'install' folder

Dear all! I recently successfully made and run pw on a new computer (Red Hat, intel compilers, mkl); Since I am interested in phonon properties I am also trying to make ph but it stops without error message after entering the QE /install folder: make[2]: Leaving directory `/home01/e1011hjm/Q

[Pw_forum] k_points generation in (crystal_b)

Dear all! I have a question regarding the generation of k_points for band plots. My cell is cubic and defined via ibrav=1 and a=5.90. Then I perform scf, nscf, bands calculation using pw.x, run band.x and plotbands to get eventually the pdf. However, when I design the k path to be K_POINTS |(

Re: [Pw_forum] NaN error in plotbandband.x - error in k-path?

Thank you so much! Sometimes the devil is in the details but usually he sits in front of the PC. Works like a charm now! Yours, Chris ___ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum

[Pw_forum] NaN error in plotbandband.x - error in k-path?

Dear All! I am trying to calculate the band structure of a (tiny) simple cubic unit cell containing 12 atoms of 5 species. I imported to structure from a CIF file via VESTA. 1) First I am running an &scf and it seems to converge. 2) Then I am running &bands and it finishes fine with