Monoclinic Crystal Structure

Queries about input and output files, running specific calculations, etc.


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apple
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Monoclinic Crystal Structure

#1 Post by apple » Thu Jul 08, 2010 2:55 pm

hi all,
would you please share with me what is the best way of optimizing a monoclinic structure. Thank you in advance,

apple
Last edited by apple on Thu Jul 08, 2010 2:55 pm, edited 1 time in total.

forsdan
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Monoclinic Crystal Structure

#2 Post by forsdan » Thu Jul 08, 2010 7:16 pm

Given that you have some reasonable starting guess for the volume, angles and the basis vectors I would either

1) Set ISIF = 4 and perform calculations for different volumes.

or

2) Increase the ENCUT and set PREC = Accurate and relax the structure with ISIF = 3.

The increased accuracy in option 2 is required to eliminate/reduce the Pulay stresses when the cell is relaxed, please see

http://cms.mpi.univie.ac.at/vasp/vasp/V ... tress.html

For more information on why option 1 is an alternative to option 2, please look at

http://cms.mpi.univie.ac.at/vasp/vasp/A ... s_two.html

Cheers,
/Dan

<span class='smallblacktext'>[ Edited Thu Jul 08 2010, 09:18PM ]</span>
Last edited by forsdan on Thu Jul 08, 2010 7:16 pm, edited 1 time in total.

apple
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Monoclinic Crystal Structure

#3 Post by apple » Sun Jul 11, 2010 4:54 pm

Thank you.
Last edited by apple on Sun Jul 11, 2010 4:54 pm, edited 1 time in total.

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