From mermaidyy at 126.com Sun Apr 12 12:28:27 2026 From: mermaidyy at 126.com (mermaidyy) Date: Sun, 12 Apr 2026 18:28:27 +0800 (CST) Subject: [QE-developers] An unsolvable bug when using EPW Message-ID: Dear Quantum ESPRESSO Developers? I have recently encountered an unsolvable bug while calculating superconductivity for a certain material system using EPW. The settings in my ?nscf.in? file are: nscf.in &control calculation = 'bands', prefix = 'NbMgB4', pseudo_dir = '../', outdir = './', wf_collect = .true., verbosity='high' / &system ibrav = 0, nat = 6, ntyp = 3, ecutwfc = 65, ecutrho = 600.0, smearing = 'mp', occupations = 'smearing', !nosym = .true., !noinv = .true., degauss = 0.05 / &electrons diagonalization = 'david', mixing_mode = 'plain', mixing_beta = 0.3, conv_thr = 1.0d-8 / ATOMIC_SPECIES Mg 24.305 Mg.pbesol-n-kjpaw_psl.0.3.0.UPF Nb 92.91 Nb.pbesol-spn-kjpaw_psl.0.3.0.UPF B 10.811 b_pbesol_v1.4.uspp.F.UPF CELL_PARAMETERS {bohr} 5.7979 0.00000 0.00000 0.00000 10.146 0.00000 0.00000 0.00000 6.3104 ATOMIC_POSITIONS crystal Mg -0.0000000000000000 0.0000000000000000 -0.0000000000000000 Nb 0.5000000000000000 0.5000000000000000 -0.0000000000000000 B -0.0000000000000000 0.3322622395511202 0.5000000000000000 B 0.5000000000000000 0.8331863993084528 0.5000000000000000 B -0.0000000000000000 0.6677377894488785 0.5000000000000000 B 0.5000000000000000 0.1668135716915483 0.5000000000000000 K_POINTS crystal 216 0.00000000 0.00000000 0.00000000 4.629630e-03 0.00000000 0.00000000 0.16666667 4.629630e-03 0.00000000 0.00000000 0.33333333 4.629630e-03 ...... 0.83333333 0.83333333 0.50000000 4.629630e-03 0.83333333 0.83333333 0.66666667 4.629630e-03 0.83333333 0.83333333 0.83333333 4.629630e-03 (which were generated using ?kmesh.pl? 6?6?6) For the phonon calculation, my ?ph.in? file is: &inputph prefix='NbMgB4', fildyn='NbMgB4.dyn.xml', fildvscf='dvscf', tr2_ph=1.0d-10, ldisp=.true., nq1 = 3, nq2 = 3, nq3 = 3, / And some relevant parameters in my ?epw.in? file are: mp_mesh_k = .true. use_ws = .true. nk1 = 6 nk2 = 6 nk3 = 6 nq1 = 3 nq2 = 3 nq3 = 3 nkf1 = 12 nkf2 = 12 nkf3 = 12 nqf1 = 6 nqf2 = 6 nqf3 = 6 / After submitting the epw job, I get the error: Error in routine createkmap (1): is this a uniform k-mesh? Then I set ??nosym = .true.?? in the ?nscf.in? file. then I get: = BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES = RANK 0 PID 6279 RUNNING AT d111 = KILLED BY SIGNAL: 6 (Aborted) After that, I removed ??nosym=.true.?? from ?nscf.in? , but EPW again reports the ??is this a uniform k-mesh??? error. If I instead use ??K_POINTS automatic?? in nscf.in? as? K_POINTS automatic 6 6 6 0 0 0 then the error becomes: inconsistent nscf and elph k-grids other methods such as? 1.K_POINTS automatic 6 6 6 1 1 1 2.Modify the grid density of k-points and q-points. 3.Comment out this line?mp_mesh_k = .true. are unable to solve the problem. No matter what I try, these errors persist. Could you please help me analyze the cause? Thank you very much for your attention! Yours Yandong Yang -------------- next part -------------- An HTML attachment was scrubbed... URL: