[CPMD-list] partial charges

[Robert fiske]

We are currently looking to do QM/MM free energy calculations using CPMD and 
gromacs.  For these calculations we wish to vary the charge of the quantum 
system.  Searching the list I read that CPMD does support partial charges, 
but that problems can arise for optimization, CPMD is not used to optimize 
the system when used with Gromacs but just to compute single point 
calculations.

Is using partial charges valid for this type of calculation?

Thank you for any assistance you can provide.

Robert Fiske
Gogonea Group
Cleveland State University

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