AMBER Archive (2007)

Subject: Re: AMBER: &dipoles output in QM/MM simulations

From: Seongeun Yang (seongeun_at_korea.ac.kr)
Date: Sat Nov 03 2007 - 00:33:58 CST


Thanks a lot for your reply.
You junst pinpointed what I'm doing and gave the answer on what I'm wondering.
I'll try later advanced population analyses, if necessary.

Seongeun

> Dear Seongeun,
> I do not believe amber has at this point more advanced population
> analysis, but they should not be too difficult to code. The full Fick
> matrix is there, overlap, etc.
>
> From the Mulliken charges, a simple linear transformation would give
> you CM3 charges (See papers by Cramer and Thrular on this). These have
> been fond by people to better reproduce solvation energies, etc.
>
> Now, I believe you want the charges to compute IR spectra, correlation
> functions, etc. In that case, Mulliken might not be totally bad, in that
> the frequencies can potentially come out all right, but your intensities
> are probably suspect.
>
> Just my 2 cents worth.
>
> a.
>
-----------------------------------------------------------------------
The AMBER Mail Reflector
To post, send mail to amber_at_scripps.edu
To unsubscribe, send "unsubscribe amber" to majordomo_at_scripps.edu