Dear Siebe and Quantum Espresso friends, According to me, the tag A in &SYSTEM has a different meaning.
See: https://www.quantum-espresso.org/Doc/INPUT_PW.html#idm231 Met vriendelijke groeten, Mit freundlichen Grüßen, With kind regards, Willem Offermans Researcher Electrocatalysis SCT VITO NV | Boeretang 200 | 2400 Mol Phone:+32(0)14335263 Mobile:+32(0)492182073 [email protected]<mailto:[email protected]> [cid:[email protected]] On 8 Oct 2019, at 17:07, Siebe Vanlommel <[email protected]<mailto:[email protected]>> wrote: Hi all, I am trying to figure out whether there is a way to scale all three unit cell vectors at once in QE using pw.x. In my input file, I am using the CELL_PARAMETERS card (in units of Angstrom) to specify a unit cell. This (https://www.mail-archive.com/[email protected]/msg19387.html) old post seems to suggest that the 'A' parameter in the &SYSTEM section acts as a scaling parameter if 'ibrav==0' and the CELL_PARAMETERS card is used to specify the lattice. I take this to mean that each lattice vector is multiplied by *A, where A is a dimensionless number. However, QE complains that: "Error in routine cell_base_init (2): lattice parameter specified twice" I've tried specifying the atomic positions in 'crystal' (fractional) coordinates and in Angstroms but to no use. Input file is attached below. I'm using QE version 6.4.1. Is the interpretation of A as a scaling parameter with these settings deprecated, or am I missing something? Thanks in advance, Siebe input file: &CONTROL title = 'cha' , calculation = 'scf' , wf_collect = .true. , etot_conv_thr = 1.0D-6 , / &SYSTEM ibrav = 0, A = 1.2, nat = 108, ntyp = 2, ecutwfc = 100 , nosym = .true. , / &ELECTRONS scf_must_converge = .true. , / CELL_PARAMETERS angstrom 13.738516409 -0.000070574 0.000007978 -6.869319180 11.897869408 -0.000009602 0.000010055 -0.000007302 14.715552482 ATOMIC_SPECIES O 15.99940 O.pbe-rrkjus.UPF Si 28.08551 Si.pbe-rrkj.UPF ATOMIC_POSITIONS crystal O 0.901932010 0.098069851 0.126854702 O 0.098068745 0.901933544 0.873144107 O 0.901940529 0.803877937 0.126862649 O 0.098062465 0.196127742 0.873139246 (...) K_POINTS gamma _______________________________________________ Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso<http://www.max-centre.eu/quantum-espresso>) users mailing list [email protected]<mailto:[email protected]> https://lists.quantum-espresso.org/mailman/listinfo/users Indien u VITO Mol bezoekt, hou aub er dan rekening mee dat de hoofdingang voortaan enkel bereikbaar is vanuit de richting Dessel-Retie, niet vanuit richting Mol, zie vito.be/route.<http://www.vito.be/route> If you plan to visit VITO at Mol, then please note that the main entrance can only be reached coming from Dessel-Retie and no longer coming from Mol, see vito.be/en/contact/locations.<http://www.vito.be/en/contact/locations> VITO Disclaimer: http://www.vito.be/e-maildisclaimer
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