Re: [QE-users] Phonon calculations with different parallelization
On 3/21/24 11:03, Chirantan Pramanik wrote: The phonon frequencies are not the same basically, they are. The differences are small (a few cm-1 at most) and mostly affect low-lying frequencies. Self-consistency is not very tight (1E-14) and may already explain the observed differences. Paolo Regards, Chirantan *From:* Paolo Giannozzi *Sent:* Thursday, March 21, 2024 11:34 AM *To:* Quantum ESPRESSO users Forum ; Chirantan Pramanik *Subject:* Re: [QE-users] Phonon calculations with different parallelization On 3/21/24 03:45, Chirantan Pramanik wrote: My Phonon calculations provide different frequency values for different parallelization on the cluster especially for the total number of processors used. Is itpossible or I am doing something very wrong? As vibrational frequency is gauge invariat how it can be possible? Thanks, Chirantan It is not possible, with one exception: zero-frequency acoustic modes that have non-zero frequencies; these can vary a lot, but they are anyway set to zero by imposing the acoustic sum rule. It might be a bug, but it is hard to say more without knowing what you exactly computed on which code version Paolo -- Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216 -- Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216 ___ 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] Phonon calculations with different parallelization
On 3/21/24 03:45, Chirantan Pramanik wrote: My Phonon calculations provide different frequency values for different parallelization on the cluster especially for the total number of processors used. Is itpossible or I am doing something very wrong? As vibrational frequency is gauge invariat how it can be possible? Thanks, Chirantan It is not possible, with one exception: zero-frequency acoustic modes that have non-zero frequencies; these can vary a lot, but they are anyway set to zero by imposing the acoustic sum rule. It might be a bug, but it is hard to say more without knowing what you exactly computed on which code version Paolo -- Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216 ___ 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] Phonon calculations with different parallelization
Dear All, My Phonon calculations provide different frequency values for different parallelization on the cluster especially for the total number of processors used. Is it possible or I am doing something very wrong? As vibrational frequency is gauge invariat how it can be possible? Thanks, Chirantan ___ 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
