Subject: G: DFT Resource Usage

From: "M. Nicklaus" <[email-masked]>
Date: Thu, 26 Mar 1998 18:34:10 -0500 (EST)

Hi,

I need information (or pointers thereto) about the resource
usage of DFT calculations in G94, specifically the B3LYP method.
(I couldn't find too much on detailed resource usage specific
for DFT in the Gaussian books.)

1. What are the CPU times spent for the HF two-electron integrals
   on the one hand vs. the functional integrals on the other hand?

2. Is any--and be it indirect--information about this ratio 
   written in the G94 output?

3. How is the decision made about in-core vs. direct calculation
   depending on the memory available?  Are the same criteria 
   applied for the HF part as for the functional part of the
   calculation?  Again, is any information about this contained
   in the G94 output?

I'll summarize useful answers to the CCL.  Thanks in advance for
any response.

Marc

------------------------------------------------------------------------
 Marc C. Nicklaus                        National Institutes of Health
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      http://rex.nci.nih.gov/RESEARCH/basic/medchem/mcnbio.htm
    Laboratory of Medicinal Chemistry, National Cancer Institute,  &
 Center for Molecular Modeling, Div. of Computer Research and Technology
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