I am trying to reproduce some result from literature, that is to calculate the free energy digram of H2O splitting on some catalyst.
so I need to calculate the free energy of H2O.
from http://www.rsc.org/suppdata/cc/c1/c1cc1 ... 13033a.pdf,
I get "The free energy of H2O in bulk water was calculated in the gas phase with a pressure of 0.035 bar, which is the equilibrium vapor pressure of H2O at 298 K." This method appeared in some other articles, too.
However, I am still confused about that. Is H2O molecular put in a large box? Obviously, it is not a crystal. Then how to exert pressure on it? I know if I set PSTRESS in INCAR, I should use ISIF=3 or ISIF=4. For a isolated molecule, there are slabs in x, y, z directions. So it doesn't make sense.
Could anyone can help me with this?
Thanks advance.
How to calculate the free energy of isolated molecule under certain pressure
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Mingtao
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How to calculate the free energy of isolated molecule under certain pressure
Last edited by Mingtao on Sun Mar 10, 2013 10:31 pm, edited 1 time in total.
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support_vasp
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Re: How to calculate the free energy of isolated molecule under certain pressure
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