Hi Malte, Yes, sorry, there is a bug in the XDM code related to the parallelization. All XDM quantities are correct with the default number of pools (i.e. mpirun -n x pw.x), so I recommend not using this for now. I'll try to get it fixed soon and let the forum know when it's done.
Best, Alberto --- Dr. Alberto Otero de la Roza Department of Chemistry, University of British Columbia, Okanagan Kelowna, British Columbia, Canada V1V 1V7 * Malte Sachs <[email protected]> [2017-08-01 15:08:58 +0200]: > Dear all, > > I have tried to perform vc-relax calculations with Quantum Espresso v6.0 > using the XDM Van-der-Waals correction. I get some strange results, because > it seems that the calculated XDM stress depends on the k-point > parallelization. As a test I performed three scf calculations using the same > input (see attached) just variing the number of k-point pools: > > 2 pools with 3 k-points: XDM stress (-33.37 -33.37 -40.79) > > 3 pools with 2 k-points: XDM stress (-58.75 -58.75 -61.19) > > 6 pools with 1 k-point: XDM stress (-117.51 -117.51 -122.37) > > The stress ratio 1: 1/2 : 1/3 is the inverse of the k-point ratio per > pool... Has somebody seen something like this before? > > Best regards, > > Malte > > -- > Malte Sachs > Anorganische Chemie, Fluorchemie > Philipps-Universität Marburg > Hans-Meerwein-Straße 4 > 35032 Marburg (Paketpost: 35043 Marburg) > Tel.: +49 (0)6421 28 - 25 39 5 > http://www.uni-marburg.de/fb15/ag-kraus/ > > &CONTROL > calculation = 'scf', > title = 'UCl6_P-3m1' > verbosity = 'high' > prefix = 'UCl6_P3' > outdir = './outdir/' > pseudo_dir = '/home/Sachsm/Promotion/Pseudos/' > tstress = .true., > wf_collect = .true. > etot_conv_thr = 1.0D-8, > forc_conv_thr = 1.0D-6 > / > &SYSTEM > ibrav = 4, > celldm(1) = 20.55532424, > celldm(3) = 0.461663392, > nat = 21, > ntyp = 2, > nbnd = 90, > occupations = 'fixed', > ecutwfc = 100, > ecutrho = 800, > vdw_corr = 'xdm', > xdm_a1 = 0.6512, > xdm_a2 = 1.4633, > / > &ELECTRONS > mixing_beta = 0.4, > mixing_mode = 'plain', > conv_thr = 1.D-10, > / > &IONS > / > &CELL > / > > K_POINTS (automatic) > 2 2 4 0 0 0 > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
