AMBER Archive (2003)

Subject: charge determination for polariable ff02 force fields

From: Xiang, Tian-Xiang (txian2_at_email.uky.edu)
Date: Fri Feb 14 2003 - 14:27:51 CST

Dear Experts and Users:

I am trying to use the polarization features of
the ff02 force field in simulations, but don't know how to
get the right sets of charges. From the paper by Cieplak et al.
(J. Comput. Chem. 22, 1048 (2001)), I know that the first step is to get
the ESP(QM)
at the level of B3LYP/cc-pVTZ. I have done this by Gaussian 98. The
second step is
to get ESP due to induced dipoles, or ESP(ind). How to do this? Anyone
has a detailed
instruction or script on this? The third step is to get the difference,
ESP(QM)-ESP(ind).
How to do this efficiently? The fourth step is to do charge fit to
ESP(QM)-ESP(ind)
using RESP. I know how to do this step. The above four steps are
iterated to get a converged set of charges.

I'd appreciate if anyone helps on steps 2 and 3. Thanks

Tian-xiang