Dear Amber experts, I would like to know your opinion about this charge
parametrization. Probably the RESP method is not intended for these
simple molecules, I can put the QM charges directly, just to know..
The system is ICH2CN, and I calculated the electrostatic potential ab
initio as usual, obtaining these point charges:
ESP charges:
1
1 C -0.898387
2 C 0.631150
3 I 0.032933
4 H 0.353024
5 H 0.353045
6 N -0.471765
When I use the ordinary RESP method, I get the following result:
4 I1 i M 3 2 1 1.540 111.208 -180.000 -0.113877
5 C1 c3 M 4 3 2 2.208 151.520 -180.000 -0.101590
6 H1 h1 E 5 4 3 1.090 105.533 -58.378 0.140478
7 H2 h1 E 5 4 3 1.090 105.521 58.407 0.140478
8 C2 c1 M 5 4 3 1.447 112.551 -180.000 0.346442
9 N1 n1 M 8 5 4 1.162 179.005 180.000 -0.411931
the charge on nitrile carbon is less than half, and the iodine changes
sign..
the latter fact can be important..I am running some preparatory
classical simulations of halogen bond.
Thanks
Lorenzo G.
--
==========================================
Lorenzo Gontrani
Research associate - EDXD group
University of Rome "La Sapienza"
ResearcherID: L-6061-2014
GSM +39 338 7615798
Email lorenzo DOT gontrani AT uniroma1 DOT it
Webpage: http://webcaminiti/gontrani.html
=========================================
Rispetta l'ambiente: se non รจ necessario, non stampare
questa e-mail
Protect the environment: do not print this e-mail, unless
necessary
_______________________________________________
AMBER mailing list
AMBER.ambermd.org
http://lists.ambermd.org/mailman/listinfo/amber
Received on Wed Apr 27 2016 - 04:00:03 PDT
