If there is no model/structure problem, then you can try to set diagonalization='cg' in &electrons namelist, although this method will decrease the calculation speed due to the poor parallel performance.
-- GAO Zhe CMC Lab, Materials Science & Engineering Department, Seoul National University, South Korea At 2012-07-18 13:30:15,"bamidele ibrahim" <bamideleibrahim at yahoo.com> wrote: Dear all, I am running scf calculation and relax with the input file below: &control calculation = 'relax', prefix='MgSe' pseudo_dir='/home/adetunji/espresso-4.3/pslibrary.0.2.5/pz/PSEUDOPOTENTIALS', outdir='./', / &system ibrav=0, nat=8, celldm(1)= 11.32, ntyp=2, ecutwfc = 50.0, / &electrons mixing_beta = 0.9 conv_thr = 1.0d-9 / &ions ion_dynamics ='bfgs' / ATOMIC_SPECIES Mg 24.305 Mg.pz-n-kjpaw.UPF Se 78.963 Se.pz-n-kjpaw.UPF CELL_PARAMETERS 0.000 0.49 0.49 0.49 0.000 0.49 0.49 0.49 0.000 ATOMIC_POSITIONS Mg 0.00000000 0.00000000 0.00000000 Mg 0.00000000 0.50000000 0.50000000 Mg 0.50000000 0.00000000 0.50000000 Mg 0.50000000 0.50000000 0.00000000 Se 0.25000000 0.25000000 0.25000000 Se 0.75000000 0.75000000 0.25000000 Se 0.75000000 0.25000000 0.75000000 Se 0.25000000 0.75000000 0.75000000 K_POINTS (automatic) 6 6 6 1 1 1 In both cases, it crashes and produces this error: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% from cdiaghg : error # 42 diagonalization (ZHEGV*) failed %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Can anybody in the house tell me what i have done wrong. Adetunji Bamidele Ibrahim(PhD Student) Department of physics,University of Agriculture, Abeokuta, Ogun State,Nigeria. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20120718/e7c44ee2/attachment.htm