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[paul.boulanger@umontreal.ca]

Hi again,

After a more careful study of your input file, I think I have found the 
problem. I plotted your structure with Jmol and found that the oxygen atoms 
all packed together (well atoms 3,4,5). If you calculate the distance between 
atom 4 and 5 we get 0.48 angstrom.

The atoms being very close, the forces most be huge. Hence, when Abinit tries 
to relax your structure, it moves the atoms very far away form each other. 
Your cell litteraly explodes. Pierre-Matthieu tried your input file and after 
8 Broyden steps the atoms had 10^5 bohr between them.

I suggest finding better initial atomic positions (remember viewing your 
input structure as many benefits). On another hand, Pierre-Matthieu suggested 
doing molecular dynamics with a very small time step, to avoid this problem. 
Unfortunatly, I don't know much about this.

Paul