Hi M, The parameter in play here is called "upscale", take a look at the description of it in input parameters list. (Also for big systems one might want to keep in mind that conv_thr is an extensive quantity) cheers - emine
On Sat, Feb 7, 2015 at 3:11 PM, MKondrin <[email protected]> wrote: > Hello! > > I try to optimize quite large structure (several tens of atoms in the > unit cell) but I can not quite get that is the criteria of convergence > to proceed for the next optimization cycle. I use QE 5.01 > > I have in the preamble of input file something like: > > &control > calculation='relax', > prefix='scf', > tstress=.true., > tprnfor=.true., > pseudo_dir = '../pseudo', > outdir='./tmp' > / > &system > ibrav=0, > celldm(1) = 12.60447, > ntyp=2, > nat=84, > ecutwfc=70, > ecutrho=800, > occupations='fixed' > / > &electrons > mixing_beta = 0.7, > conv_thr = 1.0d-6 > / > &ions > / > .... > > I suppose that the next cycle of structure optimization should occur > than the accuracy of self consistent calculations of about 1e-6 Ry. > > However in the output file I get this (this is the end of one scf cycle) > > iteration # 20 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 5.68E-10, avg # of iterations = 1.0 > > total cpu time spent up to now is 230665.4 secs > > total energy = -823.97008715 Ry > Harris-Foulkes estimate = -823.97008883 Ry > estimated scf accuracy < 0.00000279 Ry > > iteration # 21 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 5.68E-10, avg # of iterations = 4.0 > > total cpu time spent up to now is 233303.9 secs > > total energy = -823.97008869 Ry > Harris-Foulkes estimate = -823.97008855 Ry > estimated scf accuracy < 0.00000071 Ry > > iteration # 22 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 3.37E-10, avg # of iterations = 1.0 > > total cpu time spent up to now is 236012.3 secs > > total energy = -823.97008898 Ry > Harris-Foulkes estimate = -823.97008869 Ry > estimated scf accuracy < 0.00000092 Ry > > iteration # 23 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 3.37E-10, avg # of iterations = 3.5 > > total cpu time spent up to now is 238645.5 secs > > total energy = -823.97008880 Ry > Harris-Foulkes estimate = -823.97008904 Ry > estimated scf accuracy < 0.00000178 Ry > > iteration # 24 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 3.37E-10, avg # of iterations = 1.0 > > total cpu time spent up to now is 241385.7 secs > > total energy = -823.97008829 Ry > Harris-Foulkes estimate = -823.97008881 Ry > estimated scf accuracy < 0.00000147 Ry > > iteration # 25 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 3.37E-10, avg # of iterations = 3.9 > > total cpu time spent up to now is 244038.6 secs > > total energy = -823.97008797 Ry > Harris-Foulkes estimate = -823.97008835 Ry > estimated scf accuracy < 0.00000057 Ry > > iteration # 26 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 2.72E-10, avg # of iterations = 4.0 > > total cpu time spent up to now is 246730.6 secs > > total energy = -823.97008832 Ry > Harris-Foulkes estimate = -823.97008847 Ry > estimated scf accuracy < 0.00000043 Ry > > iteration # 27 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 2.03E-10, avg # of iterations = 1.0 > > total cpu time spent up to now is 249273.6 secs > > total energy = -823.97008831 Ry > Harris-Foulkes estimate = -823.97008833 Ry > estimated scf accuracy < 0.00000021 Ry > > iteration # 28 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 9.87E-11, avg # of iterations = 1.1 > > total cpu time spent up to now is 252028.1 secs > > total energy = -823.97008826 Ry > Harris-Foulkes estimate = -823.97008832 Ry > estimated scf accuracy < 0.00000017 Ry > > iteration # 29 ecut= 70.00 Ry beta=0.70 > Davidson diagonalization with overlap > ethr = 8.33E-11, avg # of iterations = 6.2 > > total cpu time spent up to now is 254596.4 secs > > End of self-consistent calculation > > > Aren't the cycles after #25 superfluous, because energy difference > between two successive steps and estimated accuracy is less than 1e-6 > Ry? What is the control parameter that help me to reduce the number of > steps ? > > Thank you in advance! > > M. V. Kondrin (High Pressure Physics Institute RAS, Troitsk, Russia) > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum >
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