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<DIV><FONT face="B Lotus" size=4>Dear Gabriele,</FONT></DIV>
<DIV><FONT face="B Lotus" size=4></FONT> </DIV>
<DIV><FONT face="B Lotus" size=4>I found the origin of the stop:</FONT></DIV>
<DIV><FONT face="B Lotus" size=4>I must NOT force any coordinates of any
atom to remain fix. I just removed " 0 0 0" after the coordinates of the first
atom and now it works at the expense that there is a whole translation of the
system along the z-direction.</FONT></DIV>
<DIV><FONT face="B Lotus" size=4>Thank you again for your kind
help.</FONT></DIV>
<DIV><FONT face="B Lotus" size=4></FONT> </DIV>
<DIV><FONT face="B Lotus" size=4>Bests,</FONT></DIV>
<DIV><FONT face="B Lotus" size=4>mahmoud</FONT></DIV>
<DIV><FONT face="B Lotus" size=4></FONT> </DIV>
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