I repeated your calculation on my computer and vc-relax was maintaining a finite value of absolute magnetization till the end of the relaxation. double check your results and in case you can confirm it for a recent version include your output and more information on the run (parallel or serial, machine, compiler, libraries...)
stefano Bryan M. Wong wrote: > Hi, > > I seem to have a problem doing "vc-relax" with the > "starting_magnetization" initialization turned on. > > I can always do a regular "relax" with the starting_magnetization > guess, and the structure will relax with a magnetic state constrained to my > *fixed* unit cell dimensions. However, when I do a *vc-relax* with > starting_magnetization set to any non-zero value, the 2nd step in the cell > relaxation always reverts to the spin-unpolarized case (and the optimization > will continue with the spin-unpolarized case). > > I have attached an example of this behavior for a simple graphene > nanoribbon. After the first step, the nanoribbon is magnetic and nonzero, > but the 2nd step reverts back to a non-magnetic initial condition. > > Is there any way around this (without constraining the magnetization to > a fixed value for all steps)? > > Thanks, > Bryan > > > > &CONTROL > calculation = 'vc-relax' , > etot_conv_thr = 1.0e-4 , > forc_conv_thr = 1.0e-3 , > tstress = .true. , > tprnfor = .true. , > / > &SYSTEM > ibrav = 8, > celldm(1) = 4.644592221, > celldm(2) = 6.70720764, > celldm(3) = 4.393200375, > nat = 10, > ntyp = 4, > ecutwfc = 60.D0 , > nosym = .false. , > nbnd = 28, > nelec = 34, > tot_charge = 0.000000, > occupations = 'smearing' , > degauss = 0.02 , > smearing = 'gaussian' , > nspin = 2 , > starting_magnetization(1) = 1.0, > starting_magnetization(2) = -1.0, > starting_magnetization(3) = 1.0, > starting_magnetization(4) = -1.0, > / > &ELECTRONS > conv_thr = 1.D-6 , > mixing_beta = 0.7D0 , > / > &IONS > ion_dynamics = 'bfgs' , > pot_extrapolation = 'second_order' , > wfc_extrapolation = 'second_order' , > trust_radius_ini = 0.2D0 , > / > ATOMIC_SPECIES > H1 1.00000 H.pbe-rrkjus.UPF > C1 12.00000 C.pbe-rrkjus.UPF > C2 12.00000 C.pbe-rrkjus.UPF > H2 1.00000 H.pbe-rrkjus.UPF > ATOMIC_POSITIONS crystal > H1 0.000000000 0.218692155 0.000000000 1 1 0 > C1 0.000000000 0.284883518 0.000000000 1 1 0 > C2 0.500000000 0.326062773 0.000000000 1 1 0 > C1 0.500000000 0.413734370 0.000000000 1 1 0 > C2 0.000000000 0.456468822 0.000000000 1 1 0 > C1 0.000000000 0.543530576 0.000000000 1 1 0 > C2 0.500000000 0.586265119 0.000000000 1 1 0 > C1 0.500000000 0.673937250 0.000000000 1 1 0 > C2 0.000000000 0.715116935 0.000000000 1 1 0 > H2 0.000000000 0.781308481 0.000000000 1 1 0 > K_POINTS automatic > 13 1 1 0 0 0 > > > ------------------------------------------------------------------------ > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum >
