[Wien] a couple questions about minimization

[Shu Miao]

Dear users,
I'm running a complex parallel calculation to minimize the
internal parameters of an H cell. I have two troubles:
1. After the scf of each changed structure was done, mini shows the
following message:
>>  (mini) PORT stopped -> exit
 :WARNING, CURVATURE CONDITION FAILED
 :WARNING, S.Y WAS  -1.9945581246343171E-004
 :WARNING, MIMIMIZATION MAY BE IN TROUBLE

Nobody in my group can tell too much about it, though they know it's a bad
thing. Can anyone kindly explain it to me what's it and how to deal with?

2. In the final structure, the atom initially sits at (0,0,0) is moved to
(0,0,0.999). Does this mean I need rebuild the cell with decreased C
parameter while keeping all the refined inter-atom distances same?

Many thanks

Shu Miao