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<div style="margin-bottom: 0in;">Dear paulatto</div>
<div style="margin-bottom: 0in;">Thanks a lot because of your attention.
I want to put graphene on substrate so I think that the van der waals
force becomes important for this case (isn't correct?). By the way I have
read the paper of M.Lazzeri & et al(Phys. Rev. B <strong>78</strong>,
081406(R) (2008)) & I know the problem of LDA & GGA
approximations(for graphene & graphite), so if there is any way to
correct them please aware
me.</div>
<div style="margin-bottom: 0in;">Well, I have to explain more about my
first question. please assume that we have two layers of graphene.
First the distance between them is 3 a.u & then it has been
changed to 10 a.u. What will happen for hartree(Uee) term in
calculations, Do you expect that it will increase or decrease?</div>
<div style="margin-bottom: 0in;">Best Regards</div>
<div style="margin-bottom: 0in;">Mehrnaz Anvari</div>
<div style="margin-bottom: 0in;">Iran University Of Science &
Technology
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