next up previous contents index
Next: Efficient relaxation from a Up: Frequently used settings in Previous: Recommended minimum setup   Contents   Index

N.B. This document is no longer maintained, please visit our wiki.

Efficient relaxation from an unreasonable starting guess

If you want to do an efficient relaxation from a configuration that is not close to the minimum, set the following values in the INCAR file (for briefness the recommended setup is lacking, see Sec. 6.2.3):

NELMIN = 5           #  do a minimum of four electronic steps
EDIFF  = 1E-2        #  low accuracy
EDIFFG = -0.3        #  accuracy of ions not too high
NSW    = 10          #  10 ionic steps in ions
IBRION =  2          #  use CG algorithm
This way only low accuracy will be required in the first few steps, but since a minimum of 5 electronic steps is done the accuracy of the calculated electronic groundstate will gradually improve. If you are a slightly advanced user you can also use the damped MD algorithm, which is usually more efficient than the CG one:
IBRION =  1 ; SMASS = 0.4  # damped MD  
POTIM  = 0.4         # time step needs to chosen with care
In this case, a too large POTIM will result in divergence.



N.B. Requests for support are to be addressed to: vasp.materialphysik@univie.ac.at