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<p>Dear users,</p>
<p>I understand that the f-sum rule can be used in order to check the reliability of results obtained via gipaw.x. In most documents I find that "the f-sum rule should be matched
<u>as good as possible</u>" , but this is rather vague to me. Can someone put a value on the error that is still acceptable?
<br>
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<p>As an example, here is the f-sum rule from a GIPAW calculations of a methyl group adsorbed on a TiO2-surface (76 atoms in total):</p>
<p>f-sum rule (should be -569.3617):<br>
-571.1240 0.0002 -0.3758<br>
0.0001 -570.9898 -0.0002<br>
-0.3808 -0.0002 -570.0995<br>
</p>
<p>Is this good enough or should it be better?</p>
<p>Thanks in advance,<br>
Laurens Siemons<br>
PhD, University of Antwerp<br>
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