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<TITLE>GRADIENT NORM NOT ZERO!</TITLE>
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<P><FONT SIZE=2 FACE="Arial">Dear MOLPRO colleagues,</FONT>
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<P><FONT SIZE=2 FACE="Arial">After numerical frequencies calculations (e.g. ccsd(t)), sometime we got the following warning:</FONT>
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<P><FONT SIZE=2 FACE="Arial">Gradient norm at reference geometry: 0.11426D-01 </FONT>
<BR><FONT SIZE=2 FACE="Arial"> ?WARNING: GRADIENT NORM NOT ZERO!</FONT>
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<P><FONT SIZE=2 FACE="Arial">Of course the imaginary frequencies would then look strange. This happens no matter how tight the geometry is converged in previous geometry optimization (e.g. grad changed from the default 3d-4 to 1d-6). Does anyone has a solution to this problem?</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Thanks a lot!</FONT>
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<P><FONT SIZE=2 FACE="Arial">Jun Li</FONT>
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