Subject: escaped charge effects of PCM model

From: "BAN FUQUIANG" <[email-masked]>
Date: Mon, 1 Oct 2001 15:01:30 AST

Dear all:

I am trying to understand the escaped charge effects of the DPCM 
(polarizable dielectric model)  solvation model. I have two questions:
(1) How the escaped charge effects are defined.
(2) How can I analyze the escaped charge effects of a DPCM 
calculation using Gaussian 98 program.

Thanks

---

From: Cory Pye <[email-masked]>
Date: Tue, 2 Oct 2001 11:52:30 -0300 (ADT)

> From Gauss's Law, the sum of the surface charges should be equal and opposite 
to the charge inside the cavity. The sum of the surface charges and the true 
charge as specified in the Gaussian input is the escaped (or outlying) charge.
It is due to the fact that some of the electron density resides outside the 
cavity.

You can avoid a good chunk of the escaped charge effects by the COSMO model
CPCM. I coded a similar solvation model in the ADF package while post-doc'ing 
in Calgary. The original genius behind the model was Klamt (now at COSMOlogic).

> calculation using Gaussian 98 program.

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