[Pw_forum] (no subject)
Dear QE users, How to choose k points of a hexagonal structure for wannier transport calculation? It is showing error when i use k points generated using utilities like kmesh.pl , kgrid and kpoints.x . -- *Nayana Devaraj* ___ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum
Re: [Pw_forum] result of phonon GRID_example 3 is not consistent with the reference
Could anyone help confirm this please? Really appreciate any help. ___ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum
Re: [Pw_forum] Run QE with space_group and "ATOMIC_POSITIONS crystal_sg"
Oh now it is clear to me. Thank you very much for your reply. On 8 October 2017 at 16:24, Paolo Giannozzi wrote: > On Sun, Oct 8, 2017 at 9:03 PM, Ricardo Afonso > wrote: > >> >> Tsung-Lung Li explained the atoms will be moved independently according >> to the forces acting on them. >> > > if they are moved "according to the forces", they are not moved > "independently", because the forces are constrained by the symmetry of the > system. > > Paolo > > >> And you said that is correct. It seems to me that somehow contradicts to >> say that this still preserves the symmetry. >> Please clarify if I'm wrong about this. Because I understand right to >> keep the symmetry the atoms should be moved not only according to their >> forces, but also preserving their coordinates, which suggests that their >> should move isotropically, right? >> >> Thank you very much, >> >> Ricardo. >> >> On 5 October 2017 at 14:09, Paolo Giannozzi >> wrote: >> >>> On Thu, Oct 5, 2017 at 4:03 PM, Tsung-Lung Li >>> wrote: >>> >>> It seems to me QE does the following. 1. Initially, QE uses space_group and the 7 inequivalent atoms in ATOMIC_POSITIONS to produce 24 atoms in the crystal unit cell. >>> >>> correct >>> >>> 2. In each subsequent geometric step of the 'relax' calculation, the 24 atoms are moved independently according to the forces acting on each atom. >>> >>> correct >>> >>> Therefore, at the end of the 'relax' calculation, the space_group=15 symmetry is not always preserved. >>> >>> not correct. Structural optimization based on forces does not break the >>> symmetry, with occasional unfortunate exceptions due to numerical noise >>> >>> Can QE only move the 7 inequivalent atoms and use space_group symmetry to construct the other 17 atoms for next geometric step? >>> >>> It could be done in principle, but it would require some extensive >>> changes to the structural optimization algorithm, with dubious advantages >>> in return. >>> >>> Paolo >>> >>> This way, the space_group symmetry will be preserved at the end of the simulation. Thank you in advance. Best Regards, Tsung-Lung Li -- &control calculation = 'relax' restart_mode = 'from_scratch' / &system space_group = 15 celldm(1) = 11.86181088389489 ! bohr celldm(2) = 2.41851202803887 celldm(3) = 0.903616377250279 celldm(5) = -0.408489773780522 ntyp = 4 nat = 7 / ATOMIC_SPECIES Ca 40.078000 Ca_pbe_v1.uspp.F.UPF S 32.065000 S_pbe_v1.2.uspp.F.UPF O 15.999400 O.pbe-n-kjpaw_psl.0.1.UPF H1.007900 H.pbe-rrkjus_psl.0.1.UPF ATOMIC_POSITIONS crystal_sg Ca 0.0 0.17050 0.25000 S 0.0 0.32727 0.75000 O 0.08319 0.27218 0.59103 O 0.19997 0.38195 0.91298 O -0.20823 0.06826 -0.07831 H -0.25800 0.08700 -0.23400 H -0.24400 0.02000 -0.07700 ___ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum >>> >>> >>> >>> -- >>> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, >>> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy >>> Phone +39-0432-558216 <+39%200432%20558216>, fax +39-0432-558222 >>> <+39%200432%20558222> >>> >>> >>> ___ >>> Pw_forum mailing list >>> Pw_forum@pwscf.org >>> http://pwscf.org/mailman/listinfo/pw_forum >>> >> >> >> >> -- >> Ricardo Afonso >> Student of Magnetism and Superconductivity Group >> Federal University of Sao Carlos >> >> ___ >> Pw_forum mailing list >> Pw_forum@pwscf.org >> http://pwscf.org/mailman/listinfo/pw_forum >> > > > > -- > Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, > Univ. Udine, via delle Scienze 208, 33100 Udine, Italy > Phone +39-0432-558216, fax +39-0432-558222 > > > ___ > Pw_forum mailing list > Pw_forum@pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- Ricardo Afonso Student of Magnetism and Superconductivity Group Federal University of Sao Carlos ___ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum
Re: [Pw_forum] Run QE with space_group and "ATOMIC_POSITIONS crystal_sg"
On Sun, Oct 8, 2017 at 9:03 PM, Ricardo Afonso wrote: > > Tsung-Lung Li explained the atoms will be moved independently according to > the forces acting on them. > if they are moved "according to the forces", they are not moved "independently", because the forces are constrained by the symmetry of the system. Paolo > And you said that is correct. It seems to me that somehow contradicts to > say that this still preserves the symmetry. > Please clarify if I'm wrong about this. Because I understand right to keep > the symmetry the atoms should be moved not only according to their forces, > but also preserving their coordinates, which suggests that their should > move isotropically, right? > > Thank you very much, > > Ricardo. > > On 5 October 2017 at 14:09, Paolo Giannozzi wrote: > >> On Thu, Oct 5, 2017 at 4:03 PM, Tsung-Lung Li >> wrote: >> >> It seems to me QE does the following. >>> >>> 1. Initially, QE uses space_group and the 7 inequivalent atoms in >>> ATOMIC_POSITIONS to produce 24 atoms in the crystal unit cell. >>> >> >> correct >> >> >>> 2. In each subsequent geometric step of the 'relax' calculation, >>> the 24 atoms are moved independently according to the forces >>> acting on each atom. >>> >> >> correct >> >> >>> Therefore, at the end of the 'relax' calculation, the space_group=15 >>> symmetry is not always preserved. >>> >> >> not correct. Structural optimization based on forces does not break the >> symmetry, with occasional unfortunate exceptions due to numerical noise >> >> >>> Can QE only move the 7 inequivalent atoms and use space_group symmetry >>> to construct the other 17 atoms for next geometric step? >>> >> >> It could be done in principle, but it would require some extensive >> changes to the structural optimization algorithm, with dubious advantages >> in return. >> >> Paolo >> >> This way, the space_group symmetry will be preserved at the end of the >>> simulation. >>> >>> Thank you in advance. >>> >>> Best Regards, >>> Tsung-Lung Li >>> >>> -- >>> &control >>>calculation = 'relax' >>>restart_mode = 'from_scratch' >>> / >>> &system >>>space_group = 15 >>>celldm(1) = 11.86181088389489 ! bohr >>>celldm(2) = 2.41851202803887 >>>celldm(3) = 0.903616377250279 >>>celldm(5) = -0.408489773780522 >>>ntyp = 4 >>>nat = 7 >>> / >>> >>> ATOMIC_SPECIES >>> Ca 40.078000 Ca_pbe_v1.uspp.F.UPF >>> S 32.065000 S_pbe_v1.2.uspp.F.UPF >>> O 15.999400 O.pbe-n-kjpaw_psl.0.1.UPF >>> H1.007900 H.pbe-rrkjus_psl.0.1.UPF >>> >>> ATOMIC_POSITIONS crystal_sg >>>Ca 0.0 0.17050 0.25000 >>>S 0.0 0.32727 0.75000 >>>O 0.08319 0.27218 0.59103 >>>O 0.19997 0.38195 0.91298 >>>O -0.20823 0.06826 -0.07831 >>>H -0.25800 0.08700 -0.23400 >>>H -0.24400 0.02000 -0.07700 >>> >>> ___ >>> Pw_forum mailing list >>> Pw_forum@pwscf.org >>> http://pwscf.org/mailman/listinfo/pw_forum >> >> >> >> -- >> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, >> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy >> Phone +39-0432-558216 <+39%200432%20558216>, fax +39-0432-558222 >> <+39%200432%20558222> >> >> >> ___ >> Pw_forum mailing list >> Pw_forum@pwscf.org >> http://pwscf.org/mailman/listinfo/pw_forum >> > > > > -- > Ricardo Afonso > Student of Magnetism and Superconductivity Group > Federal University of Sao Carlos > > ___ > Pw_forum mailing list > Pw_forum@pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222 ___ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum
Re: [Pw_forum] Run QE with space_group and "ATOMIC_POSITIONS crystal_sg"
dear Paolo, Tsung-Lung Li explained the atoms will be moved idependently according to the forces acting on them. And you said that is correct. It seems to me that somehow contradicts to say that this still preserves the symmetry. Please clarify if I'm wrong about this. Because I understand right to keep the symmetry the atoms should be moved not only according to their forces, but also preserving their coordinates, which suggests that their should move isotropically, right? Thank you very much, Ricardo. On 5 October 2017 at 14:09, Paolo Giannozzi wrote: > On Thu, Oct 5, 2017 at 4:03 PM, Tsung-Lung Li > wrote: > > It seems to me QE does the following. >> >> 1. Initially, QE uses space_group and the 7 inequivalent atoms in >> ATOMIC_POSITIONS to produce 24 atoms in the crystal unit cell. >> > > correct > > >> 2. In each subsequent geometric step of the 'relax' calculation, >> the 24 atoms are moved independently according to the forces >> acting on each atom. >> > > correct > > >> Therefore, at the end of the 'relax' calculation, the space_group=15 >> symmetry is not always preserved. >> > > not correct. Structural optimization based on forces does not break the > symmetry, with occasional unfortunate exceptions due to numerical noise > > >> Can QE only move the 7 inequivalent atoms and use space_group symmetry to >> construct the other 17 atoms for next geometric step? >> > > It could be done in principle, but it would require some extensive changes > to the structural optimization algorithm, with dubious advantages in return. > > Paolo > > This way, the space_group symmetry will be preserved at the end of the >> simulation. >> >> Thank you in advance. >> >> Best Regards, >> Tsung-Lung Li >> >> -- >> &control >>calculation = 'relax' >>restart_mode = 'from_scratch' >> / >> &system >>space_group = 15 >>celldm(1) = 11.86181088389489 ! bohr >>celldm(2) = 2.41851202803887 >>celldm(3) = 0.903616377250279 >>celldm(5) = -0.408489773780522 >>ntyp = 4 >>nat = 7 >> / >> >> ATOMIC_SPECIES >> Ca 40.078000 Ca_pbe_v1.uspp.F.UPF >> S 32.065000 S_pbe_v1.2.uspp.F.UPF >> O 15.999400 O.pbe-n-kjpaw_psl.0.1.UPF >> H1.007900 H.pbe-rrkjus_psl.0.1.UPF >> >> ATOMIC_POSITIONS crystal_sg >>Ca 0.0 0.17050 0.25000 >>S 0.0 0.32727 0.75000 >>O 0.08319 0.27218 0.59103 >>O 0.19997 0.38195 0.91298 >>O -0.20823 0.06826 -0.07831 >>H -0.25800 0.08700 -0.23400 >>H -0.24400 0.02000 -0.07700 >> >> ___ >> Pw_forum mailing list >> Pw_forum@pwscf.org >> http://pwscf.org/mailman/listinfo/pw_forum > > > > -- > Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, > Univ. Udine, via delle Scienze 208, 33100 Udine, Italy > Phone +39-0432-558216, fax +39-0432-558222 > > > ___ > Pw_forum mailing list > Pw_forum@pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- Ricardo Afonso Student of Magnetism and Superconductivity Group Federal University of Sao Carlos ___ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum
