Search found 76 matches

by new_986
Sun Jun 28, 2020 10:45 am
Forum: GW
Topic: Bang gap of RbGeCl3
Replies: 0
Views: 86

Bang gap of RbGeCl3

Dear all
Greetings...
I am trying to calculate band gap of cubic perovskite RbGeCl3, attached is my inputs and outputs. but the value is not comparable with the available results. I have tried different value of ecuts.. I don't know what is wrong..
any help please?

Thanks in advance
Nawzad
by new_986
Thu Jun 11, 2020 12:13 pm
Forum: Input file
Topic: Phase transition under pressure?
Replies: 4
Views: 124

Re: Phase transition under pressure?

Dear Eric

check that
Thanks for your help always

Best regards

Nawzad
by new_986
Sun Jun 07, 2020 11:51 am
Forum: Input file
Topic: Phase transition under pressure?
Replies: 4
Views: 124

Re: Phase transition under pressure?

Dear Eric
When i was varying lattice parameters of the non-cubic phase, i was varying in somehow to keep a/c ratio constant..
I have tried optimization at hydrostatic pressures also, The non-cubic phase was turning to almost the cubic one, means it gives me nearly the same results...

Regards

Nawzad
by new_986
Mon May 25, 2020 12:12 pm
Forum: Input file
Topic: Phase transition under pressure?
Replies: 4
Views: 124

Phase transition under pressure?

Dear all I am trying to calculate phase transition of CsSnBr3 from pm-3m cubic to p4/mbm tetragonal under pressure the cubic contains 5 atoms per unit cell while tetragonal contains 10 atoms per unit cell I have varied lattice parameters of the unit cell of both and calculated energy then I have cal...
by new_986
Sat May 16, 2020 11:06 pm
Forum: Theory
Topic: Phase transition?
Replies: 0
Views: 80

Phase transition?

Dear All I am trying to do calculations on phase transition of CsSnBr3 from cubic (pm-3m) to tetragonal (P4/mbm) I have calculated total energy with respect to pressure for both phases, then I have calculated enthalpy (Etot+pressure*Volume) for both, The graph between Enthalpy on y-axis and pressure...
by new_986
Sat May 16, 2020 1:52 pm
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

Dear Eric
I was following a specific reference for what is related to the Wyckoff position, Unfortunately the reference was not quit correct. I feel sorry for bothering you...My input file is working correctly now
Thanks a lot

Nawzad
by new_986
Tue Apr 28, 2020 11:07 am
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

I have found the correct wyckoff positions and the output file tells me the space group is correct,, everything work well except the c/a ratio becomes 1 while it suppose to keep the structure tetragonal (c/a=constant),, how to keep c/a ratio constant in abinit please? Excellent, great! For the c/a,...
by new_986
Mon Apr 27, 2020 4:02 pm
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

Dear Eric I have found the correct wyckoff positions and the output file tells me the space group is correct,, everything work well except the c/a ratio becomes 1 while it suppose to keep the structure tetragonal (c/a=constant),, how to keep c/a ratio constant in abinit please? Best regards Nawzad
by new_986
Tue Apr 14, 2020 3:22 pm
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

Dear Nawzad, The positions you sent are not for doubled cell, right? Best wishes, Eric Dear Eric I have tried to get fractional coordinates using software SPUDS, following are the resultant coordinates: Cs 4b 0.0 0.5 0.25 Pb 4c 0.0 0.0 0.0 Cl 4a 0.0 0.0 0.25 Cl 8h 0.3428 0.8428 0.0 How to translate...
by new_986
Sat Apr 11, 2020 6:43 pm
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

ebousquet wrote:
Mon Mar 30, 2020 9:44 am
Dear Nawzad,
The positions you sent are not for doubled cell, right?
Best wishes,
Eric
Dear Eric
No, it is for one unit cell, a=b not equal to c

Regards

Nawzad
by new_986
Mon Mar 16, 2020 11:08 am
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

Dear Nawzad, You need to extend the cell and break the symmetry by moving the atoms accordingly, is it what you did? Best wishes, Eric Dear Eric I have already these following extensions for perovskite 0.0 0.0 0.0 0.5 0.5 0.51 0.5 0.5 0.0 0.5 0.0 0.5 0.0 0.5 0.5 and 0.0 0.0 0.0 0.5 0.5 0.51 0.5 0.5...
by new_986
Mon Mar 09, 2020 11:44 am
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

Dear Eric
I have already tried extensions but still no relaxation happens...
Thanks a lot

Nawzad
by new_986
Tue Feb 25, 2020 9:32 am
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Re: Optimization of tetragonal perovskit???

Dear Nawzad, You indeed break the symmetries with the cell parameters but you kept the atomic positions to high-symmetry ones and it sounds your system goes back to cubic if all the atomic positions are in high-sym (and I would say as it should be for perovskites without epitaxial constraints). Alt...
by new_986
Tue Feb 25, 2020 9:19 am
Forum: Input file
Topic: MIXing coefficients for ALCHemical potentials [SOLVED]
Replies: 8
Views: 314

Re: MIXing coefficients for ALCHemical potentials [SOLVED]

The code stops at the level of the parser hence it does not enter the SCF cycle. As mentioned in the error message: Found the token NPSPALCH in the input file. This name is not one of the registered input variable names (see https://www.abinit.org/doc). NPSPALCH is an internal variable (the name st...
by new_986
Tue Feb 25, 2020 9:16 am
Forum: Input file
Topic: MIXing coefficients for ALCHemical potentials [SOLVED]
Replies: 8
Views: 314

Re: MIXing coefficients for ALCHemical potentials [SOLVED]

Dear Nawzad, To me it is not possible that the program runs a few relaxation steps without complaining about the input file and stops about a wrong input variable after passing the initial input variables test... Could you send your output file and eventually the log file? Thanks, Eric Dear Eric Yo...
by new_986
Mon Feb 24, 2020 11:47 am
Forum: Input file
Topic: Optimization of tetragonal perovskit???
Replies: 16
Views: 754

Optimization of tetragonal perovskit???

Dear all Greetings I am trying to do optimization for tetragonal phase of a perovskite specifically CsPbCl3 I give spgroup input variable which 140 due to papers but my run stops and gives me the following error: --- !ERROR src_file: symatm.F90 src_line: 201 mpi_rank: 13 message: | Largest error (ab...
by new_986
Mon Feb 24, 2020 8:28 am
Forum: Input file
Topic: MIXing coefficients for ALCHemical potentials [SOLVED]
Replies: 8
Views: 314

Re: MIXing coefficients for ALCHemical potentials [SOLVED]

Dear Eric Thanks for the reply the error message is the following --- !ERROR src_file: chkvars.F90 src_line: 403 mpi_rank: 13 message: | Found the token NPSPALCH in the input file. This name is not one of the registered input variable names (see https://www.abinit.org/doc). Action: check your input ...
by new_986
Sun Feb 23, 2020 10:29 am
Forum: Input file
Topic: MIXing coefficients for ALCHemical potentials [SOLVED]
Replies: 8
Views: 314

Re: MIXing coefficients for ALCHemical potentials [SOLVED]

Dear Jmb
Thanks for the reply
I have checked the right version inputs and it is same but still the computer stops after a couple times of optimization
Regards

Nawzad
by new_986
Tue Feb 18, 2020 9:17 am
Forum: Input file
Topic: MIXing coefficients for ALCHemical potentials [SOLVED]
Replies: 8
Views: 314

MIXing coefficients for ALCHemical potentials [SOLVED]

Dear all I want to study the effect to doping Sn into CsPbCl3, here is my input # DATASET configuration ndtset 1 # Atomic Structure #----------------- acell 5 5 5 Angstr natom 5 ntypat 3 typat 1 2 2 2 3 rprim 1 0 0 0 1 0 0 0 1 xred 0.0 0.0 0.0 0.5 0.0 0.5 0.0 0.5 0.5 0.5 0.5 0.0 0.5 0.5 0.5 prtcif 1...
by new_986
Tue Oct 22, 2019 8:35 am
Forum: Theory
Topic: theory of optic tutorial? [SOLVED]
Replies: 2
Views: 471

Re: theory of optic tutorial? [SOLVED]

Thanks Nick
by new_986
Mon Jan 28, 2019 9:13 am
Forum: Theory
Topic: theory of optic tutorial? [SOLVED]
Replies: 2
Views: 471

theory of optic tutorial? [SOLVED]

Hello everybody
What theory used to calculate linear optical properties in tutorial optic in abinit?

Thanks
by new_986
Mon Dec 17, 2018 10:08 am
Forum: Ground state
Topic: Phase transition under pressure?
Replies: 4
Views: 1034

Re: Phase transition under pressure?

ebousquet wrote:Dear Nawzad,
I would say the most general directions to break all the symmetries.
Best wishes,
Eric

Thanks Eric
I will try that

Nawzad
by new_986
Sat Dec 01, 2018 10:57 am
Forum: Ground state
Topic: Phase transition under pressure?
Replies: 4
Views: 1034

Re: Phase transition under pressure?

Dear Nawzad ABINIT performs the structural optimizations by keeping the symmetries of the initial structure. It seems that your system has the cubic symmetry (Pm-3m). If you do not allow ABINIT to leave this space group, it is normal that the system remains always cubic. Simply break the symmetries...
by new_986
Fri Nov 09, 2018 8:59 pm
Forum: Input file
Topic: Atomic structure relaxation [SOLVED]
Replies: 4
Views: 956

Re: Atomic structure relaxation [SOLVED]

Dear Nawzad, Thanks so much for your reply. What I meant was something similar to having optcell=2. However, optcell=2 allows for full relaxation subject to symmetry imposed in the initial guess structure. Here I do not know the symmetry groups of the materials of interest and wish to find those ou...
by new_986
Mon Nov 05, 2018 11:32 am
Forum: Input file
Topic: Atomic structure relaxation [SOLVED]
Replies: 4
Views: 956

Re: Atomic structure relaxation [SOLVED]

Dear cgs12
see input variables opcell and ionmove ...
best wishes

Nawzad