Re: [QE-users] sternheimer_kernel: root not converged in phonon calculation
I tell a lie - calculations don't always converge at single k-points. In fact the bands calculation for the system I'm studying fails more often than not at any given k-point (it just worked 10 times in a row on Friday - could be the crunchy effect). After more digging, part of the problem seems to be that the random wavefunctions may or may not work at any given k-point, but since there is no seeding of the randum number generator, the exact point at which calculations fail is the same for any given set of conditions but changes as the conditions change. Essentially this makes it impossible to use bands calculation over lines for this system. It is possible to calculate the bands k-point at a time with some small changes to the code (seeding the random number generator so that different random wavefunctions are used for the same calculation, not stopping the band calculation if there are too many unconverged bands but trying again with a new set of random wavefunctions) and repeating any failed calculations until they work. The most awkward problem is that when the Hamiltonian is not positive definite, the LAXlib calls MPIabort so rather more modification would be required to retry band calculations with new wavefunctions. Kind regards, Jeremy De : users de la part de RABONE Jeremy Envoyé : vendredi 22 mars 2024 16:45 À : users@lists.quantum-espresso.org Objet : Re: [QE-users] sternheimer_kernel: root not converged in phonon calculation Hello again, After some further tests (and attempts to calculated electronic band structure), there seems to be something spectacularly broken in calculations where series of q-points (phonon) or k-points (bands) are used. The points where failures occur all work fine if they are calculated as single points, but calculations along a line or over the Brillouin zone always throw one or other of the errors to do with diagonalisation (too many bands unconverged or loss of positive definiteness or root not converged) at some point. The failures all happen at the same point in any given calculation but what is weird is that one can, for example, do a band calculation with 7 k-points with 10 points along each line and it will fail at point 23 but doing the same calculation with just the line between the first 2 k-points it fails on the 4th point... Is it the case that the wavefunctions from the previous calculation are used as starting point for the next one ? If so is there a way to stop this and always restart from random wavefunctions ? Kind regards, Jeremy De : users de la part de RABONE Jeremy Envoyé : mardi 19 mars 2024 15:25 À : users@lists.quantum-espresso.org Objet : [QE-users] sternheimer_kernel: root not converged in phonon calculation Hello, I seem to be having a similar problem to one previously reported in 2022 where phonon calculation fails to converge with huge errors for a particular q point having worked fine for the gamma point. The exchange seemed to conclude that the math libraries (mkl) of a particular machine were at fault, and I'm wondering if this is also the case with the cluster I'm using. Has there been any conclusive identification of mkl libraries causing problems (I'm using intel 17.0.1.132) ? Kind regards, Jeremy ___ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples ___ Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users
Re: [QE-users] sternheimer_kernel: root not converged in phonon calculation
Hello again, After some further tests (and attempts to calculated electronic band structure), there seems to be something spectacularly broken in calculations where series of q-points (phonon) or k-points (bands) are used. The points where failures occur all work fine if they are calculated as single points, but calculations along a line or over the Brillouin zone always throw one or other of the errors to do with diagonalisation (too many bands unconverged or loss of positive definiteness or root not converged) at some point. The failures all happen at the same point in any given calculation but what is weird is that one can, for example, do a band calculation with 7 k-points with 10 points along each line and it will fail at point 23 but doing the same calculation with just the line between the first 2 k-points it fails on the 4th point... Is it the case that the wavefunctions from the previous calculation are used as starting point for the next one ? If so is there a way to stop this and always restart from random wavefunctions ? Kind regards, Jeremy De : users de la part de RABONE Jeremy Envoyé : mardi 19 mars 2024 15:25 À : users@lists.quantum-espresso.org Objet : [QE-users] sternheimer_kernel: root not converged in phonon calculation Hello, I seem to be having a similar problem to one previously reported in 2022 where phonon calculation fails to converge with huge errors for a particular q point having worked fine for the gamma point. The exchange seemed to conclude that the math libraries (mkl) of a particular machine were at fault, and I'm wondering if this is also the case with the cluster I'm using. Has there been any conclusive identification of mkl libraries causing problems (I'm using intel 17.0.1.132) ? Kind regards, Jeremy ___ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples ___ Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users
[QE-users] sternheimer_kernel: root not converged in phonon calculation
Hello, I seem to be having a similar problem to one previously reported in 2022 where phonon calculation fails to converge with huge errors for a particular q point having worked fine for the gamma point. The exchange seemed to conclude that the math libraries (mkl) of a particular machine were at fault, and I'm wondering if this is also the case with the cluster I'm using. Has there been any conclusive identification of mkl libraries causing problems (I'm using intel 17.0.1.132) ? Kind regards, Jeremy ___ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples ___ Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users
Re: [QE-users] Different results for charged cluster in PHonon 5.1 and 7.2
Hello, That's the thing - the calculations run as they should, everything is apparently as it should be but the frequencies are shifted significantly. I have done a few other tests of other charged clusters and H2O vs H3O+ and comparison with finite differences calculations and it genuinely seems that some correction for charged cells that was originally applied in PHonon is no longer applied. It is no great problem since these calculations are fine using finite differences, but I was just curious as to what has happened and whether it was intentional (i.e. should calculations that were done using the old version be considered more approximate). Kind regards, Jeremy De : users de la part de Lorenzo Paulatto Envoyé : mercredi 14 février 2024 17:23 À : users@lists.quantum-espresso.org Objet : Re: [QE-users] Different results for charged cluster in PHonon 5.1 and 7.2 Hello, On top of what Paola says, I would recommend checking the output of pw.x first. If the total energy calculation is not identical, the phonons results will be widely different. And if there is a difference in the total energy calculation, it could be traced back more easily to a change in the code. kind regards. On 14/02/2024 11:14, RABONE Jeremy wrote: Hello, I have re-run a Phonon calculation for a charged cluster that was done using version 5.1 with version 7.2 and the results are completely different; there is a large positive shift in the frequencies. Can somebody tell me what was done differently in 5.1 for charged cells ? Kind regards, Jeremy Rabone ___ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples ___ Quantum ESPRESSO is supported by MaX (www.max-centre.eu<http://www.max-centre.eu>) users mailing list users@lists.quantum-espresso.org<mailto:users@lists.quantum-espresso.org> https://lists.quantum-espresso.org/mailman/listinfo/users -- Dr. Lorenzo Paulatto IdR @ IMPMC - CNRS UMR 7590 & Sorbonne Université phone: +33 (0)1 442 79822 / skype: paulatz http://www.impmc.upmc.fr/~paulatto/ - https://anharmonic.github.io/ 23-24/423 B115, 4 place Jussieu 75252 Paris CX 05 ___ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples ___ Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users
[QE-users] Different results for charged cluster in PHonon 5.1 and 7.2
Hello, I have re-run a Phonon calculation for a charged cluster that was done using version 5.1 with version 7.2 and the results are completely different; there is a large positive shift in the frequencies. Can somebody tell me what was done differently in 5.1 for charged cells ? Kind regards, Jeremy Rabone ___ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples ___ Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users
[QE-users] Convergence problem with hydroxide
Hello, I have just started a project using QE, and have a question regarding a hydroxide ion in a box. When I first tried to do a relaxation with conv_thr = 1.0d-8, it started off like it was going to converge and then suddenly the convergence went all over the place. Changing all of the other parameters made no difference, but reducing conv_thr to 1.0d-6 stops the scf step before the problem and the calculation completes. There also seems to be some effect of the randomised starting wavefunctions even with conv_thr = 1.0d-6 (sometimes converges, sometimes goes all triplets). When surrounding the ion with a water cage, the calculation works with no problems. If I switch to a spin polarized calculation, with conv_thr = 1.0d-8 it seems determined to converge to a triplet state with the first antibonding orbital occupied, and does so with no difficulty is the magnetization is set to 2. I recall there were sometimes issues in DFT when the order of state energies changes during a calculation - is this what is happening here and is there a way to get passed the problem or do I just have to be content with a reduced threshold ? A S2- ion in a box does something similar - seemingly converging to triplet with a d-state occupied, and even when surrounded by a water cage it fails to converge in a singlet state (although in this case one might question the validity of the calculation). I'm using SG15 norm-conserving pseudopotentials but the PAW pseudopotential seems to do the same thing. Regards, Jeremy ___ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples ___ Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list users@lists.quantum-espresso.org https://lists.quantum-espresso.org/mailman/listinfo/users
