Vasp tips 1
Full geometry optimization Performing a volume optimization (e.g. ISIF = 3 ) in VASP requires to reset the Wavefunction.
This is to control the Pulay Stress.
To avoid such issue you can run consecutive geometry optimizations (cancelling the WAVECAR and copying CONTCAR in POSCAR) until the Pulay stress is minimized and the calculation converges in few (i.e. <7) steps.
In my experience this method allows to find a good (i.e. low in energy) minima of the structures you consider, but it comes to the price of considerable distortions.
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