Search found 18 matches

by ryne60
Fri Apr 26, 2019 10:58 am
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi ketong, In addition, do you have some suggestions or tricks about the setting of "iprcel", "diemac" and "diemix"? unfortunately, I don't! Sorry, I didn't do much test for those parameters. Since my systems are too big, testing those parameters will be time consuming....
by ryne60
Thu Apr 25, 2019 12:46 pm
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi ketong,

Yes, it's been deleted since then! But, since my systems are big, the calculation time (scfcv time) is still long but now "comparable" to VASP because the first few scf cycles now take significantly less time.
by ryne60
Wed Apr 03, 2019 11:14 am
Forum: Theory
Topic: Unitary transformation matrix wavefunctions
Replies: 0
Views: 561

Unitary transformation matrix wavefunctions

Hi All, from the theory part of ABINIT discussing wavefunctions, in the section "Symmetry Properties": https://docs.abinit.org/theory/wavefunctions/#symmetry-properties , Eqn. (8) shows how to transform wavefunctions of k-points connected by crystal symmetries. I have a couple of questions...
by ryne60
Wed Mar 27, 2019 9:35 am
Forum: Ground state
Topic: tetrahedron table [SOLVED]
Replies: 2
Views: 651

Re: tetrahedron table [SOLVED]

Hi Matthieu,

thanks for the answer!

Yeah, I know that prtdos has the gaussian option too, but I need the tetrahedron table for post-processing calculations.

If I may give a feedback for a future version of ABINIT; Could the table be output too in some file (by some variable or by default)? Thanks!
by ryne60
Mon Mar 25, 2019 9:40 am
Forum: Ground state
Topic: tetrahedron table [SOLVED]
Replies: 2
Views: 651

tetrahedron table [SOLVED]

Hi all,

according to the manual prtdos is used to calculate DOS with the tetrahedron method. Is there a way to see the tetrahedron table used in the aforementioned calculation? In other words, does ABINIT output this table in some output file?

Thanks!
by ryne60
Mon Mar 25, 2019 9:35 am
Forum: Ground state
Topic: spin-orbit calculation with HSE functional
Replies: 2
Views: 483

Re: spin-orbit calculation with HSE functional

Thanks, Eric!

By any chance, do you know when ABINIT will be able to include SOC within HSE functionals?

Ryky
by ryne60
Fri Mar 22, 2019 1:45 pm
Forum: Ground state
Topic: spin-orbit calculation with HSE functional
Replies: 2
Views: 483

spin-orbit calculation with HSE functional

Hi all, I've been trying to do a spin-orbit calculation with a HSE functional, but the calculation always stopped with the following error: Hartree-Fock option can be used only with option nspinor=1. Is there a way to make spin-orbit calculations compatible with any HSE functional in ABINIT? Thanks!
by ryne60
Fri Mar 01, 2019 1:58 pm
Forum: Input file
Topic: restarting scf calculation with a different set of kpoints [SOLVED]
Replies: 2
Views: 556

restarting scf calculation with a different set of kpoints [SOLVED]

Hello,

is it possible to restart an scf calculation with a different set of kpoints but using the wavefunction data from the previous calculation?

Thanks!
by ryne60
Wed Jan 23, 2019 9:44 am
Forum: Ground state
Topic: different occopts give different qualitative result
Replies: 1
Views: 486

different occopts give different qualitative result

Dear all, I've been calculating a system with two slightly different structures, say structures A & B. The first set of calculations using occopt 6 and resulted in the total energy of A (EA) smaller than the total energy of B (EB). However, when I use occopt 7 the results show that EB < EA. Has ...
by ryne60
Fri Jan 11, 2019 1:02 pm
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi woffermans, it seems the culprit was iprcel; because of this, the first few SCF cycles took so many hours. In my opinion, somehow the following note about iprcel in the online manual is a bit misleading: For non-homogeneous relatively large cells iprcel = 45 will likely give a large improvement o...
by ryne60
Fri Dec 21, 2018 9:16 am
Forum: Pseudopotentials and PAW datasets
Topic: pw_ecut in JTH PAW dataset
Replies: 0
Views: 914

pw_ecut in JTH PAW dataset

Hi All, I use a JTH PAW dataset from my calculation and the file lists the following parameter: <pw_ecut low="12.00" medium="12.00" high="12.00"/>. If I understand correctly this pw_ecut is the recommended value to bet set as "ecut" in the input file. Am I rig...
by ryne60
Fri Dec 14, 2018 5:47 pm
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi Eric, I made some trial calculations with similar kind of systems but with a lot smaller size of unit cell; i.e. still 2D systems with 2 atoms per unit-cell, and thus the timing was a lot faster. In these cases, the setup with iprcel 44 finished faster than cases with other iprcel values. So I ju...
by ryne60
Thu Dec 13, 2018 2:27 pm
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi woffermans,

I also tried with both calculations using the Fermi smearing (ISMEAR -1 & occopt 3) and the conclusion regarding the calculations' speed doesn't not change much!
by ryne60
Thu Dec 13, 2018 9:05 am
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi woffermans, If I understand you correctly, then you need more time per electronic cycle as well as more cycles for your ABINIT calculation, compared to VASP. Moreover the difference is significant. It is not just a couple of minutes and 3 cycles less or more. Yes, that's correct; for the comparis...
by ryne60
Mon Dec 10, 2018 10:06 am
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi onion2440,

after 300 cycles the maximum energy diff is around 10 Ha, which is >> 1e-9 Ha. So even if I increase toldfe to, let's say, 1e-7, the overall calculation is still very expensive. Maybe any clue how to improve/speed-up the calculation time per cycle?
by ryne60
Fri Dec 07, 2018 3:17 pm
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Re: Improving calculation performance?

Hi Woffermans, Thanks for the reply! The calculation is slow in terms of time per SCF-cycle and convergence speed; it took around 2 hours per SCF-cycle and the calculation isn't converged after 300 cycles. Also please kindly find attached the PAW potential I use! And any further suggestion is welcom...
by ryne60
Thu Dec 06, 2018 9:55 am
Forum: Ground state
Topic: Improving calculation performance?
Replies: 17
Views: 2797

Improving calculation performance?

Hi All, I'm a new member in the forum; thanks for providing this forum. Currently, I'm trying to do a ground-state calculation for a nanoribbon system consisting of 30 atoms per cell with the following SCF-related parameter setup: # SCF cycle parameters ecut 12. pawecutdg 30. nstep 300 nband 150 tol...