Optimum memory allocation in GAUSSIAN94

["C.F. Matta" <mattacf %! at !% mcmail.cis.McMaster.CA>]

 Hello everybdy,
 In GAUSSIAN94, I noticed that the job CPU time as recorded in the log file
 increases when I allocate too much memory (instead of decreasing).
 For example, a geometry optimization of benzene at the restricted
 Hartree-Fock level using a 3-21G basis set on a LINUX 5.2 platform
 with a PENTIUM III 600MHz processor (768MBs RAM), took the following
 times:
 	200 MB ----> 1 minutes 18.5 seconds
         600 MB ----> 2 minutes 11.6 seconds
 I noticed the same with other systems as well, larger memory=slower
 job.  There must be a way to estimate the optimum memory allocation for a
 specific job.
 I would much appreciate your help.  Thank you very much.
 (I will summarize)
 Cherif
 ___________________________________________________________________________
   Cherif F. Matta		    	  tel. (905) 525-9140 ext. 22502
   Chemistry Department                    fax  (905) 522-2509
   McMaster University                               _______________________
   Hamilton, Ontario, CANADA L8S 4M1.                | * "You'll always miss
 ....................................................| 100% of the shots you
  Member of the Board of Governors of the University | don't take".Anonymous
 ___________________________________________________________________________