selective relaxation of cell parameters

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rgc
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selective relaxation of cell parameters

#1 Post by rgc » Thu Jan 17, 2008 7:45 am

Hi

is it possible to relax one particular cell parameter (e.g. cz) and leave the others (ax, ay, az, bx, by, bz, cx, cy) fixed?

of course it is always possible to build a E vs cz curve, with everything else constant, then fit to a polynomial and find the minimum. But I am wondering whether there is an automatic way of doing this constrained relaxation in vasp... Do "F F T" kind of flags work for cell parameters?

thanks!
Last edited by rgc on Thu Jan 17, 2008 7:45 am, edited 1 time in total.

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selective relaxation of cell parameters

#2 Post by admin » Mon Jan 28, 2008 10:33 am

no, you can either keep the cell shape completely fixed (only V varying, but c/a and the angles are kept constant) or relax all cell parameters simutaneously (shape relaxed completely) if you want to do it automatically (by using the appropriate ISIF)
Last edited by admin on Mon Jan 28, 2008 10:33 am, edited 1 time in total.

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