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<div>Dear all
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<div>I have some fundamental questions.
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<div>1.If I want to achieve the equilibirium value of
lattice paramrters (such as a, c,...) is it possible to replace bulk
modulues calculations with vc-rx?
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<div>2.when I use vc-rx for my material most of the time after 300 stpes the
stress becomes approximately zero(-0.6-0.6) but energy doesn't
converge. I don't pay attention just use the cell parameters &
atomic positions to do scf calculations. I tried to achieve convergency in
scf calculation with changing ecutwf & k-points. Now I think it couldn't
be true & I have to optimize my ecutwfc during vc-rx calculation
(Is it true?) what about k-point ,where could I optimize it?
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