Dear ???, One possibility that comes to my mind is to proceed as follows:
1 - First make a few supercells of pure graphene, each with a different size, all without the hydrogen atom, and evaluate their total energies per atom and/or bands, in order to make sure that the cell you'll use on step 2 is large enough to remove spurious border effects. 2 - Once you get a cell that's large enough, then evaluate it with the hydrogen atom and check the forces acting on the H atom. 3 - Now try to use a larger cell with the hydrogen, and evaluate the forces again on the H atom. 4 - If the cell is large enough so that no border effects are present and the hydrogens are not interfering with each other, then the forces on step 2 and 3 should be the same. Hope it helps. Giovani M. Faccin UFMS - Brazil 2011/4/26 ??? <tfcao at theory.issp.ac.cn> > Dear QE users: > I want to construct a supercell of graphene with one Hydrogen absorbed on > it , and my question is how can I choose the supercell properly so that the > interaction between Hydrogens can be neglected . Any suggestions will be > greatly appreciated . > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > > -- Giovani -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110426/47fc64a3/attachment.htm