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PSTRESS = [real]
Description: This flag controls whether Pulay corrections are added to the stress tensor or not. In molecular dynamics calculations it controls the pressure.
If the PSTRESS tag is specified VASP will add this stress to the stress tensor, and an energy to the energy. This allows the user to converge to a specified external pressure. Before using this tag please read the section Energy vs volume Volume relaxations and Pulay stress