Subject: Thermodynamic integration

From: Jonathan Arthur <[email-masked]>
Date: Tue, 11 Mar 1997 14:27:36 +1100 (EDT)

Hello all,

I am trying to perform a molecular dynamics calculation of the free energy 
for the mutation of a water molecule into a methane molecule in 
solution. I am using the thermodynamic integration technique. Although I 
have been trying for quite a while, gradually finding the bugs in my code, 
I have still not been able to reproduce the literature values for this 
reaction.

I am starting to suspect that I may not have a correct understanding of 
how this technique is used. While the many references I have consulted 
talk of 'accumulating the partial derivative dU/dlambda' they do not 
describe exactly what this partial derviative is in terms of the 
positions, velocites etc that can be accumulated each time step.

Could someone please give me some advice and/or point me in the direction 
of a good paper, some code or another source which deals with the 'nuts 
and bolts' of writing code to perform a thermodynamic integration in 
molecular dynamics? 

Thanks for your help.

Jonathan 
_______________________________________________________________
Jonathan Arthur                       Theoretical Chemistry
e-mail:    [email-masked]  School of Chemistry (F11)
telephone: +61-2-9351-2733            The University of Sydney
fax:       +61-2-9351-3329            NSW 2006 AUSTRALIA
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