Subject: Re: CCL:AO based DFT codes

From: [email-masked] (Eugene Fleischmann)
Date: Tue, 12 Jul 94 12:54:58 EDT

> From [email-masked] Tue Jul 12 12:04 EDT 1994
> Subject: CCL:AO based DFT codes
> To: [email-masked]
> Cc: [email-masked] (Hans-Ueli Suter)
> 
> Dear Netters,
> 
> I would be very happy to hear something about the current 
> use and the experiences of some AO based  desity functional
> codes. As far as I see this includes the programs
> DMol (Delley), G92/DFT (Pople), DeFT and DeMon and
> ADF.  For these there are the following two questions:
> 
> (i) Is this list complete, which program should be addeed?
> 
> (ii) What program are you using, what is your experience
>       with it. how fast, how userfriendly and how stable
>      is your program?
> 
> I will try to summarize the answers and submit them to the
> net, if requested.
> 
>                             sorry, for wasting your time,
> 
>                               Hans Ulrich  Suter
>                               CSCS, Manno, Switzerland.
> 

Greetings, Prof. Suter.  With regard to your inquiry:

> (i) Is this list complete, which program should be addeed?

The only addition to your list is:  DGauss, from Cray Research, Inc.

> (ii) What program are you using, what is your experience
>      with it. how fast, how user-friendly and how stable
>      is your program?

I use DGauss regularly, for obvious reasons.  It is a VERY user-friendly
DFT program as a stand-alone code, and even MORE user-friendly when used
with the GUI for Silicon Graphics known as:  UniChem.  DGauss is VERY
fast on Cray vector hardware, and it is also fast on SGI workstations.

The program uses gaussian functions, in the spirit of standard "ab initio"
programs today, to build the density and solve the Kohn-Sham equations.
In its present implementation, DGauss uses an all-electron non-relativistic
Hamiltonian.  The major functions of DGauss include geometry optimizations
for stationary points (minima and saddle points) on a potential energy
hypersurface.  These optimizations are carried out using analytical first 
derivatives.  Until the next release, vibrational frequencies as well as
infrared intensities are computed with finite difference techniques.  For
fixed or optimized geometries, DGauss evaluates molecular properties such 
as Mulliken charges, multipole moments, molecular orbitals, electron densities,
spin densities, and electrostatic potentials.  At present, SCF calculations 
can be carried out on the local spin density (LSD) functional level, or at 
the non-local (NLSD) level using Becke-Perdew or Becke-Stoll-Preuss-Pavlidou 
gradient corrections after the SCF or Becke-Perdew or Becke-Lee-Yang-Parr 
corrections self-consistently.  DGauss calculates molecular orbitals (MOs) 
and the corresponding orbital energies.  It is designed to take full advantage 
of the current knowledge of vector and parallel algorithms in the evaluation 
of integrals and other computationally demanding numerical procedures, such as 
the calculation of the exchange-correlation terms which are calculated 
numerically on a finite grid.

For more information about DGauss and/or UniChem please send mail to any of
the following individuals at Cray Research, Inc:

Dr. George Fitzgerald        [email-masked]
Dr. Thomas Raeuchle          [email-masked]
Dr. Eugene Fleischmann       [email-masked]

Best Wishes,

Gene

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
	Eugene D. Fleischmann, Ph.D.
	Computational Chemist
	Cray Research, Inc.		(609) 252-1250
	121 Commons Way			[email-masked]
	Princeton, NJ  08540
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