Thanks for the reply, Uwe
the same job (identical start orbitals plus identical VV10 treatment) leads to almost identical results but with quite different timings - none of the described usual "NewBie faults" are responsible for the described behaviour
the calculations are significantly speeded up, if the already mentioned lines appear in the output:
using self-consistent NL method
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You are using the DFT-NL method please cite
Vydrov, O. A.; Van Voorhis, T.; J. Chem. Phys. 2010 133, 244103
Hujo, W.; Grimme, S.; J. Chem. Theory Comput. 2011, 7, 3866
Functional parameter b X.XX YY
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I just wanted to know, what the reason behind this favourable speedup is and how one can opt in general for the faster VV10 treatment - a look into the source code would certainly be helpful, which however cannot be granted to a common user ...
Please take a reasonably large molecule (not water please) and see for yourself the difference in wall-times for two runs:
(A) $dft functional wb97m-v; $doscnl or $donl AND
(B) $dft functional wb97m; $doscnl or $donl
I would be more than happy to hear if you have managed to replicate the different timings for otherwise identical runs (except wb97m-v vs wb97m).
Cheers, Paul