Subject: summary: global minimum

From: Zhi-Xiang Wang <[email-masked]>
Date: Sat, 30 Sep 2000 21:42:02 -0400 (EDT)

My original question is:

   How to find a global minimum for a cluster with around 20 atoms.

Acknowledgment:
  I appreciate greatly the answers from the following colleagues.

   Pradipta ---- [email-masked]
   Jim      ---- [email-masked]
   Igor Shamovsky [email-masked]
   Bernd [email-masked]
   Aileen----- [email-masked] 

Summary
  (1)  Pradipta wrote: 
    There are a number of methods to find global minimum structure. 
Because of its importance in various fields, the literature is spread over
a wide variety of journals. I think the most useful methods are:
    Simulated annealing, Genetic algorithm, multicanonical algorithm.
-huge number of papers have been published using those ( especially with
the first two) algorithms. But it is very important what kind of potential
you want to use for your systems. I am at present using full quantum
mechanical calculation for some systems and  unless the above mentioned 
algorithms are supplemented with a local optimization routine, it is very
difficult to get anything. Even in general it may be a good idea to use 
local optimization technique with global optimization technique.

  (2) Jim  suggested
     Try Tinker.  You can find it at:
     http://dasher.wustl.edu/tinker/
  (3) Igor told me
     The simulated annealing approach might be very efficient for your 
system
  (4) Bernd informed me
     one method I can suggest is Genetic Algorithms and their descendants;
for this, you may want to check out my web page (see below), in particular
J.Comput.Chem. 20 (1999) p.1752 and Z.Phys.Chem. 214 (2000) 1251.
  (5) Aileen asked me
     I am interested in the replies ... can you please forward me any 
information you get from the list?
  (6) I recommend the websites 
      http://fandango.ch.cam.ac.uk
      and http://brian.ch.cam.ac.uk