NWCHEM runs with low %CPU


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Hi Ranez,
If you are running a conventional SCF or DFT calculation NWChem will write out the 2-electron integrals to a file. For larger jobs this requires enormous amounts of I/O and typically results in the processors spending most of their time waiting for the disk. If this is the case please switch to using integral direct procedures. To do this in an SCF calculation use:

   scf
direct
,,,
end

In a DFT calculation (obviously):

   dft
direct
...
end

If that does not help, please send me your input file (Hubertus DOT vanDam AT pnnl.gov).
Best wishes, Huub