Changing the Volume is the same as changing the hydrostatic pressure, therefore, the Volume optimization will give you the pressure at a certain Volume, (take care if you have free parameters for the atom sites, this may lead to "internal" pressure) you may also check the original papers on the "equation of state" by Birch , Murnaghan and others (just search PRB), indeed, form the output of the eosfit you may plot the lattice parameter as function of pressure.
Ciao Gerhard ==================================== Dr. Gerhard H. Fecher Institut of Inorganic and Analytical Chemistry Johannes Gutenberg - University 55099 Mainz ________________________________________ Von: wien-bounces at zeus.theochem.tuwien.ac.at [wien-bounces at zeus.theochem.tuwien.ac.at]" im Auftrag von "Ghosh SUDDHASATTWA [ssghosh at igcar.gov.in] Gesendet: Mittwoch, 18. Mai 2011 04:47 Bis: 'A Mailing list for WIEN2k users' Betreff: [Wien] Volume Optimization under Constant External Pressure (3 GPa to 30 GPa) Dear Wien2k users, Can anybody suggest as to how do we optimize the volume of crystal under constant external pressure in Wien2k? I would like to vary the external pressure from 3 GPa to 30 GPa. How do we input the pressure in the calculations Thanks Suddhasattwa