[QE-users] "vc-relax" and "relax" with hybrids
Giuseppe Mattioli
giuseppe.mattioli at ism.cnr.it
Thu Apr 11 14:16:54 CEST 2019
Sorry, too short answer before
Transition levels can be compared with several kinds of
opto-electronic spectroscipy (XPS, absorption, luminescence, ...).
They can be considered as a sort of "less than first order" MBPT
calculations, which use total energies of neutral and charged species
to describe optoelectronic processes and defect concentrations at
thermal equilibrium (see Van de Walle's review). Hybrid functionals
are suitable for this purpose. You must be only careful to correctly
estimate (there are several ways) the realignment of the valence band
maximum (or whatever potential reference you use) between neutral and
charged supercells.
HTH
Giuseppe
Lukas Razinkovas <lukas.razinkovas at ftmc.lt> ha scritto:
> Thank You, Giuseppe
>
>> If you are calculating ionization energies and/or electron affinities
>> no. Total energies for charged and neutral supercells are not additive
>> because of PBC.
>
> We are working with localized states of defect electrons.
> So i think it should be possible to excite single Kohn--Sham orbital.
>
>> You may also test the new implementation of SCDM localization
>
> I still don't know what it is. Gonna do some reading...
>
>
> Lukas
>
>
>
>
> On Wed, Apr 10, 2019 at 3:19 PM Giuseppe Mattioli <
> giuseppe.mattioli at ism.cnr.it> wrote:
>
>>
>> I wish to add a further question to exx developers. Is it
>> possible/complicated to implement a restart possibility from a
>> calculation with ecutfock=A as a starting guess (for potential and
>> wfc) of a calculation, having same ecutwfc and ecutrho, same k-points
>> and with ecutfock=B>A?
>> Thanks to all
>> Giuseppe
>>
>> Giuseppe Mattioli <giuseppe.mattioli at ism.cnr.it> ha scritto:
>>
>> >> However, as I understand they are a bit outdated?
>> >
>> > Well, not at all IMHO. In the "roaring twenties" of GGA, US PPs
>> > guaranteed a significant speed up of calculations, but the density
>> > cutoff was almost the same of NC. VASP steered towards PAW some
>> > years ago, and all the EXX machinery has been built to be
>> > PAW-compliant. But there is nothing "outdated" in norm-conserving,
>> > and the density cutoff may be the actual bottleneck of EXX
>> > calculations. The ecutfock variable is a very clever tunable
>> > parameter in this regard. You can verify that if ecutwfc is well
>> > converged, then ecutfock=ecutwfc is a sensible choice for *very
>> > fast* geometry optimizations, and ecutfock=1.5~2*ecutwfc is a
>> > sensible choice for properties calculation. ONCV pseudopotentials
>> > are not that "hard" (80 Ry should be a sensible ecutwfc for carbon),
>> > give them a try.
>> >
>> > HTH
>> > Giuseppe
>> >
>> >> Few additional questions if You don't mind:
>> >> - Should I expect constrained orbital calculations (delta SCF) work well
>> >> with hybrids?
>> >
>> > If you are calculating ionization energies and/or electron
>> > affinities no. Total energies for charged and neutral supercells are
>> > not additive because of PBC.
>> >
>> >> - Any suggestions for hybrid parallelisation? We have shared memory 36
>> core
>> >> mashine with hyperthreading (72 threads).
>> >> System size is 200-500 carbon atoms + defect.
>> >
>> > I'm not an expert of k-points parallelization with hybrids. If your
>> > system is large (and your system seems to be quite large) and you
>> > use gamma-only sampling, then you can perform a preliminary test
>> > (e.g. a sinle point calculation of a relevant system) with band
>> > parallelization. You may also test the new implementation of SCDM
>> > localization
>> >
>> > Experimental version of SCDM localization with k-points, activated like
>> for
>> > k=0 by specifying in &system namelist a value > 0 for "localization_thr".
>> >
>> > HTH
>> > Giuseppe
>> >
>> > Lukas Razinkovas <lukas.razinkovas at ftmc.lt> ha scritto:
>> >
>> >> Thank You, Paolo and Giusepe
>> >>
>> >> It is really awesome to get response from You :). I will try norm
>> >> conserving pseudopotentials.
>> >> However, as I understand they are a bit outdated?
>> >>
>> >> Few additional questions if You don't mind:
>> >> - Should I expect constrained orbital calculations (delta SCF) work well
>> >> with hybrids?
>> >> - Any suggestions for hybrid parallelisation? We have shared memory 36
>> core
>> >> mashine with hyperthreading (72 threads).
>> >> System size is 200-500 carbon atoms + defect.
>> >>
>> >> Thanks for Your time,
>> >> Lukas
>> >>
>> >>
>> >>
>> >> On Wed, Apr 10, 2019 at 1:26 PM Giuseppe Mattioli <
>> >> giuseppe.mattioli at ism.cnr.it> wrote:
>> >>
>> >>>
>> >>> That is: you should use NC pseudopotentials! EXX works very well if
>> >>> you learn a couple of further tricks (ecutfock, adaptive_thr).
>> >>> HTH
>> >>> Giuseppe
>> >>>
>> >>> Paolo Giannozzi <p.giannozzi at gmail.com> ha scritto:
>> >>>
>> >>>> The crash is due to a stupid error (a missing argument) in a call to
>> the
>> >>>> "errore" routine, but the routine is called because forces with USPP
>> and
>> >>>> PAW are not currently implemented with hybrid functionals
>> >>>>
>> >>>> Paolo
>> >>>>
>> >>>>
>> >>>> On Wed, Apr 10, 2019 at 11:53 AM Lukas Razinkovas <
>> >>> lukas.razinkovas at ftmc.lt>
>> >>>> wrote:
>> >>>>
>> >>>>> Dear QE users and developers,
>> >>>>>
>> >>>>> I have read about Adaptively Compressed Exchange Operator (ACE)
>> approach
>> >>>>> to hybrid
>> >>>>> functionals and that it is implemented in PWSCF code. This motivates
>> >>>>> transition from VASP
>> >>>>> to QE code for our research calculations. We are working with crystal
>> >>>>> defects and are interested in modeling excited states.
>> >>>>>
>> >>>>> However it seems that only "scf" calculations are possible. Is it
>> right?
>> >>>>> I have tried "vc-relax" and "relax" calculations and it failed.
>> >>>>>
>> >>>>> *Input file:*
>> >>>>>
>> >>>>> &CONTROL
>> >>>>> calculation = 'vc-relax' ,
>> >>>>> restart_mode = 'from_scratch' ,
>> >>>>> outdir = 'tmp' ,
>> >>>>> pseudo_dir = '../../psps/' ,
>> >>>>> prefix = 'diamond' ,
>> >>>>> verbosity = 'high'
>> >>>>> /
>> >>>>> &SYSTEM
>> >>>>> ibrav = 1,
>> >>>>> celldm(1) = 6.755024314,
>> >>>>> nat = 8,
>> >>>>> ntyp = 1,
>> >>>>> ecutwfc = 45 ,
>> >>>>> ecutrho = 350 ,
>> >>>>> input_dft = HSE06,
>> >>>>> nqx1 = 4, nqx2 = 4, nqx3 = 4
>> >>>>> /
>> >>>>> &ELECTRONS
>> >>>>> diagonalization = 'david' ,
>> >>>>> /
>> >>>>> &IONS
>> >>>>> /
>> >>>>> &CELL
>> >>>>> /
>> >>>>> ATOMIC_SPECIES
>> >>>>> C 12.01070 C.pbe-n-kjpaw_psl.1.0.0.UPF
>> >>>>> ATOMIC_POSITIONS alat
>> >>>>> C 0.000000000 0.000000000 0.000000000
>> >>>>> C 0.500000000 0.500000000 0.000000000
>> >>>>> C 0.000000000 0.500000000 0.500000000
>> >>>>> C 0.500000000 0.000000000 0.500000000
>> >>>>> C 0.250000000 0.250000000 0.250000000
>> >>>>> C 0.750000000 0.750000000 0.250000000
>> >>>>> C 0.750000000 0.250000000 0.750000000
>> >>>>> C 0.250000000 0.750000000 0.750000000
>> >>>>> K_POINTS automatic
>> >>>>> 4 4 4 0 0 0
>> >>>>>
>> >>>>>
>> >>>>> *gives error:*
>> >>>>>
>> >>>>> forrtl: severe (174): SIGSEGV, segmentation fault occurred
>> >>>>> Image PC Routine Line
>> >>>>> Source
>> >>>>> pw.x 0000000000D0C1D3 Unknown Unknown
>> >>> Unknown
>> >>>>> libpthread-2.17.s 00007F9B508AF5D0 Unknown Unknown
>> >>> Unknown
>> >>>>> pw.x 0000000000B9ED47 errore_ 10
>> >>>>> error_handler.f90
>> >>>>> pw.x 00000000005A8E2F setup_ 137
>> >>>>> setup.f90
>> >>>>> pw.x 0000000000579E23 run_pwscf_ 99
>> >>>>> run_pwscf.f90
>> >>>>> pw.x 000000000040AA85 MAIN__ 98
>> >>>>> pwscf.f90
>> >>>>> pw.x 000000000040A8E2 Unknown Unknown
>> >>> Unknown
>> >>>>> libc-2.17.so 00007F9B501F33D5 __libc_start_main Unknown
>> >>>>> Unknown
>> >>>>> pw.x 000000000040A7E9 Unknown Unknown
>> >>> Unknown
>> >>>>> forrtl: severe (174): SIGSEGV, segmentation fault occurred
>> >>>>> Image PC Routine Line
>> >>>>> Source
>> >>>>> pw.x 0000000000D0C1D3 Unknown Unknown
>> >>> Unknown
>> >>>>> libpthread-2.17.s 00007F08180CB5D0 Unknown Unknown
>> >>> Unknown
>> >>>>> pw.x 0000000000B9ED47 errore_ 10
>> >>>>> error_handler.f90
>> >>>>> pw.x 00000000005A8E2F setup_ 137
>> >>>>> setup.f90
>> >>>>> pw.x 0000000000579E23 run_pwscf_ 99
>> >>>>> run_pwscf.f90
>> >>>>> pw.x 000000000040AA85 MAIN__ 98
>> >>>>> pwscf.f90
>> >>>>> pw.x 000000000040A8E2 Unknown Unknown
>> >>> Unknown
>> >>>>> libc-2.17.so 00007F0817A0F3D5 __libc_start_main Unknown
>> >>>>> Unknown
>> >>>>> pw.x 000000000040A7E9 Unknown Unknown
>> >>> Unknown
>> >>>>>
>> >>>>> What are the main reasons for this error/behavior? Is it possible to
>> >>>>> enable this functionality?
>> >>>>>
>> >>>>> Another side question is: is is possible to use constrained orbital
>> >>>>> calculations (delta SCF) with hybrids?
>> >>>>>
>> >>>>>
>> >>>>> Lukas
>> >>>>> _______________________________________________
>> >>>>> users mailing list
>> >>>>> users at lists.quantum-espresso.org
>> >>>>> https://lists.quantum-espresso.org/mailman/listinfo/users
>> >>>>
>> >>>>
>> >>>>
>> >>>> --
>> >>>> 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
>> >>>
>> >>>
>> >>>
>> >>> GIUSEPPE MATTIOLI
>> >>> CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
>> >>> Via Salaria Km 29,300 - C.P. 10
>> >>> I-00015 - Monterotondo Scalo (RM)
>> >>> Mob (*preferred*) +39 373 7305625
>> >>> Tel + 39 06 90672342 - Fax +39 06 90672316
>> >>> E-mail: <giuseppe.mattioli at ism.cnr.it>
>> >>>
>> >>> _______________________________________________
>> >>> users mailing list
>> >>> users at lists.quantum-espresso.org
>> >>> https://lists.quantum-espresso.org/mailman/listinfo/users
>> >>>
>> >
>> >
>> >
>> > GIUSEPPE MATTIOLI
>> > CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
>> > Via Salaria Km 29,300 - C.P. 10
>> > I-00015 - Monterotondo Scalo (RM)
>> > Mob (*preferred*) +39 373 7305625
>> > Tel + 39 06 90672342 - Fax +39 06 90672316
>> > E-mail: <giuseppe.mattioli at ism.cnr.it>
>> >
>> > _______________________________________________
>> > users mailing list
>> > users at lists.quantum-espresso.org
>> > https://lists.quantum-espresso.org/mailman/listinfo/users
>>
>>
>>
>> GIUSEPPE MATTIOLI
>> CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
>> Via Salaria Km 29,300 - C.P. 10
>> I-00015 - Monterotondo Scalo (RM)
>> Mob (*preferred*) +39 373 7305625
>> Tel + 39 06 90672342 - Fax +39 06 90672316
>> E-mail: <giuseppe.mattioli at ism.cnr.it>
>>
>> _______________________________________________
>> users mailing list
>> users at lists.quantum-espresso.org
>> https://lists.quantum-espresso.org/mailman/listinfo/users
>>
GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
Via Salaria Km 29,300 - C.P. 10
I-00015 - Monterotondo Scalo (RM)
Mob (*preferred*) +39 373 7305625
Tel + 39 06 90672342 - Fax +39 06 90672316
E-mail: <giuseppe.mattioli at ism.cnr.it>
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