ABINIT Discussion Forums

Dear colleagues, We have a problem with interpreting my results. We have calculated the delithiated form of a layered solid Li2MnSiO4 (in essence 2D inorganic framework MnSiO4) with PBE, PW91 and PBESol functional. We found that for PBESol there is a strong repulsion between layers so that they move...

hi
use input from tutorial, like tgw1_9.in and edit it
bests, Maxim

Dear abinit users,

Is it true that the GW calculations require the powerful computer? My computer freezes.

Bests, Maxim.

Dear ABINIT users!

I wan to simulate phase transition at room temperature. During this phase transition one cation should occupy the position of vacancy. Which ensemble and/or ionmov should i use?

Best wishes, Maxim.

Check your input coordinated. Do not use "#" in coordinates block.

Dear Abinit users! with our modest career in the study of materials (mol %) 75ZrO2 + 12.5CeO2 + 12.5Al2O3, we need your help to simulate this type of material within the framework of any code. In particular, we do not understand which cell to select and how to arrange the atoms there. Best wishes, D...

Thank you Alain!

your recipe helped us to install abinit!

this is our recipe for installing abinit 7.0.5 on ubuntu-12.04 x64 (intel core 2 quad) viewtopic.php?f=3&t=1387&p=6477#p6477

a recipe for installing abinit 7.0.5 on ubuntu-12.04 x64 (intel core 2 quad) : 1) just after installing ubuntu disable all updates in ubuntu first (click "Dash Home" shortcut in upper-right corner and type "update" and press enter, then select "Update Manager" and then ...

nanohub is quite fast, but there are only troullier martins pseudopotentials (these pseudos sometimes give incorrect results http://forum.abinit.org/viewtopic.php?f=7&t=957&p=3048&hilit=troullier+paw#p3048 ), and nanohub's admins do not respond to our requests to allow the possibility to...

yes, you right, I mean I want nanohub's implementation of abinit become clearer There is no ability to upload own pseudos in nanohub - just TM. Because I can not upload PAW pseudos, I can not use LDA + U of ABINIT - without LDA + U some calculations are totally incorrect. Maybe I should change the ...

Dear users and developers, please register here https://nanohub.org/
and vote at https://nanohub.org/wishlist/resource/2 ... onus&tags=
to enable LDA + U support of ABINIT in nanohub - your vote will help to make ABINIT free and popular!!!


Best wishes, Maxim

I agree with ljludwig - test ecut and ngkpt to see a convergence.
Maybe you need better convergence criteria - use toldfe 1.0d-12 or tolwfr 1.0d-12 or tolvrs 1.0d-22 like in tpaw1_4.in, also try LDA+U using paw psps (paw tutorials) from http://www.abinit.org/downloads/PAW2 . Maybe LDA+U approach allows to fix incorrect band results

Thank you very much, I will surely check it out

I seem to understand it myself. To find out whether a particular etsut is enough for geometry optimization, I have to check convergence of forces in ecut, right?

Because you use nsym=1 (this blocks symmetry finder of abinit), abinit will always recognize your structure as primitive triclinic, even if it has symmetry. Maybe you can take your final optimized coordinates and re-run with nsym=0 (with symmetry finder enabled) to see which symmetry your optimized ...

"It is STRONGLY suggested first to optimize the ionic positions without cell shape and size optimization (optcell=0), then start the cell shape and size optimization from the cell with relaxed ionic positions." - maybe for metals too. Maybe for metals full optimization is not required (but...

to break ALL symmetries use nsym -1 (but this will require more kpoints and CPU time - it is so when using kptrlen and prtkpt 1 - for other kpoints settings maybe too - check it by test run and look at *.out file). It seems that all is OK (but I can't check xred - to do this plot your structure in e...

Also, concerning diemac, setting it wrong doesn't wreck the calculations, just makes the initial preconditioning step less efficient. For a metal leave it at its default, for a semiconductor like Si use 10 or so, for a wide gap insulator use 3. And what if we are dealing with ferroelectrics - their...

If you have windows then maybe 2install java proceed e. g. m nanohub requires rprim - so you should put rprim 1.0000000000E+00 0.0000000000E+00 0.0000000000E+00 0.0000000000E+00 1.0000000000E+00 0.0000000000E+00 0.0000000000E+00 0.0000000000E+00 1.0000000000E+00 in case if you have ortogonal system,...

I forgot to tell you - are you sure that these shiftk and ngkpt are suitable for your structure? I'm not sure - for proper kpoint grid remove shiftk and ngkpt and set prtkpt 1, and set kptrlen to 60-70, see http://forum.abinit.org/viewtopic.php?f=8&t=96&p=300&hilit=prtkpt+1+kptrlen#p300 ...

Have you performed convergence in ecut? Put pawecutdg at least twice bigger than ecut. Remove ixc, occopt and tsmear. Your cell is very big - is it a supercel? If yes, tnan ngkpt should be less dense. Try another ngkpt (e. g. 4 4 4 for 1 unit cell, but if you have e. g. 2x2x2 supercell, then it shou...

Try another psp (e. g. FHI) - note ecut should be different. You can try PAW psps (http://www.abinit.org/downloads/PAW2/AT ... index.html) - it could be even better - see examples for Tutorial PAW 1.

Best wishes, Maxim.

Pls give me your output file. Remove nband - this warning will disappear, but abinit will set it's own nband, which is more than your 120 bands. Run without nband and look at "occ" in output file - then set nband to number of filled bands.

Best wishes, Maxim.

Dear maryamsajedi!

For geom. optim. replace "xred" with "xangst", set occopt to 1, remove ndtset and jdtset - I can not understand in the input file that will change in your datasets?
If you use PAW pseudopotentials, then iscf=17 is correct, otherwise remove it or set it to 7.

I have a general question.

If I want to perform geometry optimization, then in general I have to use toldfe 10-12, but for ecut, the convergence with accuracy within 1mHa is enough (or such accuracy can not be required)? Which test for ecut should be performed?

Best wishes, Maxim.