Hello everyone,
I have a problem for making POSCAR for free energy calculation. A compound ABC4 crystalized cubic structure with fm-3m symmetry (z=4). The atom position is A:4a; B:4b; C:32f (1/2 occupancy).
Who can tell me how should I do if I want to calculate total energy?
How make POSCAR if atom take a half site
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wei
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How make POSCAR if atom take a half site
Last edited by wei on Wed Jun 22, 2005 11:01 pm, edited 1 time in total.
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admin
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How make POSCAR if atom take a half site
If in a crystal only half of the sites of a sublattice are occupied, you have to construct a larger supercell, containing at least one occupied C site and one vacancy (site not occupied) in sublattice C. Please be aware that this sublattice is periodically repeated, i.e. it corresponds to an ordered structure.
Last edited by admin on Fri Jun 24, 2005 12:04 pm, edited 1 time in total.