[Pw_forum] Total energy diverges in cell relaxation

[Nicola Marzari]

Hui Tang wrote:
> Dear all,
> 
> I'm trying to do cell relaxation on my Mg-Boron systems. For some of the 
> structures, I got extremely strange results. The total energy diverges 
> starting from some ionic step. For example, here are the total energy in 
> each ionic step for one of the problematic run:
> 

Two suggestions

1) are atoms overlapping much more than they should ? I.e. are these
new configurations reasonable, or are core overlaps very significant ?
The pseudopotential approximation breaks down if cores overlap (a lot).

2) is it a bug/memory overrun ? Take the first configuration with
much lower energy, and rerun that from scratch. Do you get an
energy that looks like -41.7 Ry, or much lower ?

			nic



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