Geometry Optimisations

Dear esmuigors
esmuigors said in Unexpectedly cannot get the geometry after optimization: KEYWORD EXTPRT NOT ALLOWED:

Should I only take the atoms labelled by "T" if the lattice is tetragonal, and which ones are to be taken in case of an orthorombic one? Or does "T"'and "F" stand just for "TRUE"'and "FALSE"?

You are correct T and F stand for 'TRUE' and 'FALSE'.

esmuigors said in Unexpectedly cannot get the geometry after optimization: KEYWORD EXTPRT NOT ALLOWED:

I am actually talking about the standard runPcry23 script. Perhaps it should not be like that? Or should I modify this script?

That script already contain the few line of codes I suggested you, if not feel free to modify it and add those lines.

esmuigors said in Unexpectedly cannot get the geometry after optimization: KEYWORD EXTPRT NOT ALLOWED:

Actually, I have now tried using only the "T"-labeled atoms and got this error:

ERROR **** geometry **** FORMAT ERROR IN INPUT DECK

I checked the input on top of the CS2_B1WC.pob_tzvp_rev2_gamma_onlyT.out file it seems like you are defining six atoms in the asymmetric unit, but only two atomic positions are specified in the input.

CRYSTAL 0 0 0 64 6.34350113 5.54788046 9.71085545 6. ! Definitions of the number of atoms in the asymmetric unit 6 0.000000000000e+00 0.000000000000e+00 -5.000000000000e-01 16 2.303037287581e-17 3.119080311720e-01 1.207617820468e-01 ATOMSYMM ...

The number of atoms in the asymmetric unit and the position specified should always match.

I hope this helps you,

Best,

Thanks for your response, aerba.
ATOMREMO works but when you calculate the defect formation energies you end with values (for anion vacancies) that are higher than with using GHOSTS or the ATOMSUBS, with the latter values agreeing more with published defect formation energies.

Hi,

The FINALRUN option works fine in P-CRYSTAL: that sentence in the Manual must be a leftover from the past, sorry for that.

Can you elaborate on how the optimized structures are unreasonable? Is it just for the underestimation of the computed band gap or also for some structural aspects? In this case, it would help if you could show us the "expected" structure, as well as the one you obtain from the optimization.

GiacomoAmbrogio Great! It works now! Thanks a lot!

Thank you very much. Now it works without any issue. I was not aware of the necessity to change this parameter as I did not encounter any issue with other calculations I have done due to it being 0 0 0.

Hi Othmen!

I think that you have a problem in the geometry sections of your input files. When dealing with monoclinic structures, only one angle (beta) has to be specified as alfa and gamma are 90 by default, see page 22 of Crystal User's Manual. Furthermore, in input1 the atomic coordinates are missing, while in input2 94 atoms coordinates are written but you specified that 95 atoms are present.

Let me know if you have other problems 🙂

Thank you very much for the detailed explanation—this really helped clarify things for me! The plot and your explanation made it all very clear.

Many thanks for your detailed explanation and for checking the code — that definitely clarifies things. I really appreciate your help!

thank you