Alternatively, you can calculate using the frozen phonon method. Prasenjit IISER Pune
From: "users" <users@lists.quantum-espresso.org> To: "users" <users@lists.quantum-espresso.org> Sent: Wednesday, May 15, 2024 3:49:18 AM Subject: Re: [QE-users] Phonon calculation with DFT-D3 correction ph.x currently does not support the three-body terms with the D3 dispersion correction. You can turn it off with the dftd3_threebody tag in pw.x, and follow the three step procedure you outlined in your email. If you want to include the three-body terms, you can use the supercell approach (e.g., phonopy) instead of DFPT with ph.x. Three-body terms tend to have a pretty small effect in my experience, but that's system-dependent, in principle, and you might want to test it. Refer to the original D3 papers for a discussion. Three-body terms are not used at all in VASP, for reference (but they're hidden in the source code). I also generally recommend using D3 with BJ damping or D3M/D3M-BJ instead of the standard "zero damping" D3. (dftd3_version flag in pw.x). Omar A. Ashour UC Berkeley On May 14, 2024, at 2:51 PM, Jing Lian Ng <jingl...@utexas.edu> wrote: BQ_BEGIN Hello all, I am currently trying to perform phonon calculation with DFT-D3 correction. Based on what I read from d3hess.x documentation, I believe I can include dispersion effects on vibrational frequencies by: 1. Relax / Scf calculation 2. run d3hess.x 3. run ph.x However, I encounter an error on step2, with the error message being: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% task # 28 from pbcgdisp : error # 1 Atom displacement not implemented with the threebody term %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% My input file for scf is as follows: ########################################################################## / &SYSTEM ntyp = 1 nat = 2 ibrav = 0 ecutwfc = 100 ecutrho = 400 vdw_corr = 'DFT-D3' / &ELECTRONS mixing_mode = 'plain' mixing_beta = 0.3 / &IONS / &CELL / ATOMIC_SPECIES H 1.008 H.upf CELL_PARAMETERS angstrom 5.21657500000000 0.00000000000000 0.00000000000000 0.00000000000000 6.04926000000000 0.00000000000000 -6.40884630521040 0.00000000000000 36.38325638013446 ########################################################################## Can someone advise on what could be the possible error? Thanks! -- Best regards, Jing Lian Ng , PhD Student Wang Material Group The University of Texas at Austin | [ http://che.utexas.edu/ | McKetta Department of Chemical Engineering ] | [ https://wangmaterialsgroup.com/ | Wang Materials Group ] _______________________________________________ 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 BQ_END _______________________________________________ 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
_______________________________________________ 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