Dear Giovanni, As per your suggestion I performed calculations with ecutrho 8 times ecutwfc, obtaining following results 30 -932.77949435 1314.9516 40 459.04 7m51.69s 40 -932.78411921 1314.9516 40 459.17 12m10.64s 50 -932.78290292 1314.9516 40 458.79 16m20.76s 60 -932.78405904 1314.9516 40 458.76 20m21.45s 70 -932.78361561 1314.9516 72 458.85 57m33.02s 80 -932.78379443 1314.9516 40 458.68 32m52.95s 90 -932.78384952 1314.9516 40 458.90 39m24.40s 100 -932.78383671 1314.9516 40 458.73 43m 3.29s 110 -932.78386666 1314.9516 40 458.83 47m23.76s 120 -932.78385073 1314.9516 40 458.81 58m39.28s 130 -932.78388792 1314.9516 40 458.74 1h 5m 140 -932.78391298 1314.9516 40 458.82 1h12m 150 -932.78388192 1314.9516 40 458.80 1h21m The fluctuations are still there but now less in comparisions (see graph) Right now I am testing for 10x to see if fluctations reduce. >From graph of 8x plot I feel ecutwfc=70 Ry and ecutrho=560 Ry seems a good candidate for convergence. But it has higher number of Kpoints compared to ecutwfc=80 Ry and also consumes more time what do you suggest or will data from 10x run be more conclusive?
Thanks for your help. Adwait Mevada, Ph.D. Student, Gujarat University, Gujarat, India. On Fri, Oct 23, 2015 at 9:09 PM, adwait mevada <[email protected]> wrote: > Dear Giovanni, > Thanks for the prompt response, I will do as you suggested. > The above data was obtained without fixing ecutrho to480 (it was > commented) . I felt that may be a lower kpoint grid or wrong smearing might > be the source. > I will do as you suggested and get back to you. > Thanks again. > Adwait > Ph.D. Student, > Gujarat University, > Gujarat, India. > On 23-Oct-2015 8:56 pm, "Giovanni Cantele" <[email protected]> > wrote: > >> one of the problems that you might be running across is that you keep >> ecutrho fixed. That means that with ecutwfc=30, ecutrho/ecutwfc=16, whereas >> with ecutwfc=120, the same ratio is 4. The latter is definitely too small >> for ultrasoft pseudo potentials, that you are including in your >> calculation. In other words, you might be comparing values of the total >> energies with different convergence levels with respect to ecutrho, which >> can be the origin (or a partial explanation) of the oscillations you find. >> >> I would try (maybe this will not solve your problem!) to retry the test >> as a function of ecutwfc, as you did, but keeping the ecutrho/ecutwfc ratio >> (rather than the ecutrho variable) constant, to a more or less safe value >> (e.g. 8). >> >> Giovanni >> >> > On 23 Oct 2015, at 17:05, adwait mevada <[email protected]> >> wrote: >> > >> > Dear All, >> > I am trying to find optimal ecutwfc for CaMg2. >> > As a first step i varied ecutwfc from 30-150 but i found that >> > energy was fluctuating >> > I cannot decide what to set for ecutrho if my ecutwfc is fluctuating >> > , what can be the reason for this? any help in this regard is >> appreciated. >> > >> > note : i am not finding ecutwfc for equilibrium volume. >> > >> > I am attaching png output of gnuplot for it. >> > >> > data for various ecutwfc >> > ecut energy vol kpoints stress time. >> > 30 -932.78387473 1314.9516 40 459.00 7m 4.75s >> > 40 -932.78292968 1314.9516 40 458.52 10m35.69s >> > 50 -932.78368793 1314.9516 40 458.74 14m22.97s >> > 60 -932.78388413 1314.9516 40 458.90 17m48.05s >> > 70 -932.78547210 1314.9516 40 457.91 25m37.98s >> > 80 -932.78563717 1314.9516 40 459.77 29m17.84s >> > 90 -932.78419457 1314.9516 40 459.42 35m28.98s >> > 100 -932.78387315 1314.9516 40 458.78 37m40.76s >> > 110 -932.78425940 1314.9516 40 458.38 41m34.44s >> > 120 -932.78459959 1314.9516 40 458.94 52m35.88s >> > 130 -932.78422725 1314.9516 72 459.24 2h 0m >> > 140 -932.78394222 1314.9516 72 458.91 2h 3m >> > 150 -932.78396419 1314.9516 72 458.69 2h30m >> > my input file is: >> > C=9 >> > A=5 >> > for ECUT in 30 40 50 60 70 80 90 100 ; do >> > cat > camg2e$ECUT.in << EOF >> > &control >> > calculation = 'scf' >> > prefix='camg2e$ECUT', >> > tstress = .true. >> > tprnfor = .true. >> > / >> > &system >> > ibrav=4, a=$A ,c=$C ,nat=12, ntyp=2, >> > ecutwfc=$ECUT ! ,ecutrho=480, >> > occupations='smearing',smearing="mv",degauss=0.02, >> > / >> > &electrons >> > diagonalization='david' >> > mixing_mode = 'plain' >> > mixing_beta = 0.7 >> > conv_thr = 1.0d-8 >> > / >> > ATOMIC_SPECIES >> > Mg 24.305 Mg.pw91-np-van.UPF >> > Ca 40.078 Ca.pw91-nsp-van.UPF >> > ATOMIC_POSITIONS crystal >> > Ca 0.3333333 0.6666667 0.0668052 >> > Ca 0.3333333 0.6666667 0.4331948 >> > Ca 0.6666667 0.3333333 0.5668053 >> > Ca 0.6666667 0.3333333 0.9331947 >> > Mg 0.0000000 0.0000000 0.0000000 >> > Mg 0.0000000 0.0000000 0.5000000 >> > Mg 0.3397683 0.1698842 0.2500000 >> > Mg 0.8301158 0.6602317 0.2500000 >> > Mg 0.1698842 0.8301158 0.7500000 >> > Mg 0.8301158 0.1698842 0.2500000 >> > Mg 0.1698842 0.3397683 0.7500000 >> > Mg 0.6602317 0.8301158 0.7500000 >> > K_POINTS automatic >> > 8 8 4 1 1 1 >> > EOF >> > mpirun -np 4 pw.x -in camg2e$ECUT.in > camg2e$ECUT.out >> > ENERGY=`grep ! camg2e$ECUT.out | cut -b 33-49` >> > VOL=`grep volume camg2e$ECUT.out | cut -b 33-45 ` >> > KP=`grep points= camg2e$ECUT.out | cut -b 25-31` >> > TIME=`grep "PWSCF " camg2e$ECUT.out | cut -b 37-47` >> > STRESS=`grep "total stress" camg2e$ECUT.out | cut -b 72-78` >> > FOR=`grep "Total force " camg2e$ECUT.out` >> > echo "$ECUT $ENERGY $ALAT $VOL $KP $STRESS $TIME $FOR" >> > sleep 60 >> > echo "$ECUT $ENERGY $ALAT $VOL $KP $STRESS $TIME $FOR" >> >> camg2r480.dat >> > done >> > >> > Thank you for your help in advance >> > >> > -- >> > -Adwait >> > Ph.D. Student, >> > Gujarat University, >> > Gujarat, India. >> > <camg2ecut.png>_______________________________________________ >> > Pw_forum mailing list >> > [email protected] >> > http://pwscf.org/mailman/listinfo/pw_forum >> >> -- >> >> Giovanni Cantele, PhD >> CNR-SPIN >> c/o Dipartimento di Fisica >> Universita' di Napoli "Federico II" >> Complesso Universitario M. S. Angelo - Ed. 6 >> Via Cintia, I-80126, Napoli, Italy >> e-mail: [email protected] >> Phone: +39 081 676910 >> Skype contact: giocan74 >> >> ResearcherID: http://www.researcherid.com/rid/A-1951-2009 >> Web page: http://people.na.infn.it/~cantele >> >> >> >> _______________________________________________ >> Pw_forum mailing list >> [email protected] >> http://pwscf.org/mailman/listinfo/pw_forum >> > -- -Adwait 'I Wonder!...The Empty Cup' On Fri, Oct 23, 2015 at 9:09 PM, adwait mevada <[email protected]> wrote: > Dear Giovanni, > Thanks for the prompt response, I will do as you suggested. > The above data was obtained without fixing ecutrho to480 (it was > commented) . I felt that may be a lower kpoint grid or wrong smearing might > be the source. > I will do as you suggested and get back to you. > Thanks again. > Adwait > Ph.D. Student, > Gujarat University, > Gujarat, India. > On 23-Oct-2015 8:56 pm, "Giovanni Cantele" <[email protected]> > wrote: > >> one of the problems that you might be running across is that you keep >> ecutrho fixed. That means that with ecutwfc=30, ecutrho/ecutwfc=16, whereas >> with ecutwfc=120, the same ratio is 4. The latter is definitely too small >> for ultrasoft pseudo potentials, that you are including in your >> calculation. In other words, you might be comparing values of the total >> energies with different convergence levels with respect to ecutrho, which >> can be the origin (or a partial explanation) of the oscillations you find. >> >> I would try (maybe this will not solve your problem!) to retry the test >> as a function of ecutwfc, as you did, but keeping the ecutrho/ecutwfc ratio >> (rather than the ecutrho variable) constant, to a more or less safe value >> (e.g. 8). >> >> Giovanni >> >> > On 23 Oct 2015, at 17:05, adwait mevada <[email protected]> >> wrote: >> > >> > Dear All, >> > I am trying to find optimal ecutwfc for CaMg2. >> > As a first step i varied ecutwfc from 30-150 but i found that >> > energy was fluctuating >> > I cannot decide what to set for ecutrho if my ecutwfc is fluctuating >> > , what can be the reason for this? any help in this regard is >> appreciated. >> > >> > note : i am not finding ecutwfc for equilibrium volume. >> > >> > I am attaching png output of gnuplot for it. >> > >> > data for various ecutwfc >> > ecut energy vol kpoints stress time. >> > 30 -932.78387473 1314.9516 40 459.00 7m 4.75s >> > 40 -932.78292968 1314.9516 40 458.52 10m35.69s >> > 50 -932.78368793 1314.9516 40 458.74 14m22.97s >> > 60 -932.78388413 1314.9516 40 458.90 17m48.05s >> > 70 -932.78547210 1314.9516 40 457.91 25m37.98s >> > 80 -932.78563717 1314.9516 40 459.77 29m17.84s >> > 90 -932.78419457 1314.9516 40 459.42 35m28.98s >> > 100 -932.78387315 1314.9516 40 458.78 37m40.76s >> > 110 -932.78425940 1314.9516 40 458.38 41m34.44s >> > 120 -932.78459959 1314.9516 40 458.94 52m35.88s >> > 130 -932.78422725 1314.9516 72 459.24 2h 0m >> > 140 -932.78394222 1314.9516 72 458.91 2h 3m >> > 150 -932.78396419 1314.9516 72 458.69 2h30m >> > my input file is: >> > C=9 >> > A=5 >> > for ECUT in 30 40 50 60 70 80 90 100 ; do >> > cat > camg2e$ECUT.in << EOF >> > &control >> > calculation = 'scf' >> > prefix='camg2e$ECUT', >> > tstress = .true. >> > tprnfor = .true. >> > / >> > &system >> > ibrav=4, a=$A ,c=$C ,nat=12, ntyp=2, >> > ecutwfc=$ECUT ! ,ecutrho=480, >> > occupations='smearing',smearing="mv",degauss=0.02, >> > / >> > &electrons >> > diagonalization='david' >> > mixing_mode = 'plain' >> > mixing_beta = 0.7 >> > conv_thr = 1.0d-8 >> > / >> > ATOMIC_SPECIES >> > Mg 24.305 Mg.pw91-np-van.UPF >> > Ca 40.078 Ca.pw91-nsp-van.UPF >> > ATOMIC_POSITIONS crystal >> > Ca 0.3333333 0.6666667 0.0668052 >> > Ca 0.3333333 0.6666667 0.4331948 >> > Ca 0.6666667 0.3333333 0.5668053 >> > Ca 0.6666667 0.3333333 0.9331947 >> > Mg 0.0000000 0.0000000 0.0000000 >> > Mg 0.0000000 0.0000000 0.5000000 >> > Mg 0.3397683 0.1698842 0.2500000 >> > Mg 0.8301158 0.6602317 0.2500000 >> > Mg 0.1698842 0.8301158 0.7500000 >> > Mg 0.8301158 0.1698842 0.2500000 >> > Mg 0.1698842 0.3397683 0.7500000 >> > Mg 0.6602317 0.8301158 0.7500000 >> > K_POINTS automatic >> > 8 8 4 1 1 1 >> > EOF >> > mpirun -np 4 pw.x -in camg2e$ECUT.in > camg2e$ECUT.out >> > ENERGY=`grep ! camg2e$ECUT.out | cut -b 33-49` >> > VOL=`grep volume camg2e$ECUT.out | cut -b 33-45 ` >> > KP=`grep points= camg2e$ECUT.out | cut -b 25-31` >> > TIME=`grep "PWSCF " camg2e$ECUT.out | cut -b 37-47` >> > STRESS=`grep "total stress" camg2e$ECUT.out | cut -b 72-78` >> > FOR=`grep "Total force " camg2e$ECUT.out` >> > echo "$ECUT $ENERGY $ALAT $VOL $KP $STRESS $TIME $FOR" >> > sleep 60 >> > echo "$ECUT $ENERGY $ALAT $VOL $KP $STRESS $TIME $FOR" >> >> camg2r480.dat >> > done >> > >> > Thank you for your help in advance >> > >> > -- >> > -Adwait >> > Ph.D. Student, >> > Gujarat University, >> > Gujarat, India. >> > <camg2ecut.png>_______________________________________________ >> > Pw_forum mailing list >> > [email protected] >> > http://pwscf.org/mailman/listinfo/pw_forum >> >> -- >> >> Giovanni Cantele, PhD >> CNR-SPIN >> c/o Dipartimento di Fisica >> Universita' di Napoli "Federico II" >> Complesso Universitario M. S. Angelo - Ed. 6 >> Via Cintia, I-80126, Napoli, Italy >> e-mail: [email protected] >> Phone: +39 081 676910 >> Skype contact: giocan74 >> >> ResearcherID: http://www.researcherid.com/rid/A-1951-2009 >> Web page: http://people.na.infn.it/~cantele >> >> >> >> _______________________________________________ >> Pw_forum mailing list >> [email protected] >> http://pwscf.org/mailman/listinfo/pw_forum >> > -- -Adwait 'I Wonder!...The Empty Cup'
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