From: |
giovanni \\at// sg2.csrsrc.mi.cnr.it (Giovanni Scalmani) |
Date: |
Tue, 7 Jan 1997 09:42:44 -0800 |
Subject: |
Electrostatic_effects_in_molecular_crystals |
Dear friends,
I am wondering about the following problem:
I would like to model - by means of ab-initio calculations -
the electrostatic effects on a single molecule due to the
crystalline environment within a molecular crystal, i.e.
I would like to perform a (possibly high level) calculation
of a single molecule's electronic structure under the
influence of a neighbouring molecules' charge distribution.
An iterative procedure should be necessary to attain
self-consistency between the ab-initio charge distribution
of the reference molecule and the neighbouring molecules'
charge distribution, which will be in turn derived from the
reference molecule's wavefunction.
Since I have no deep knowledge of crystallography, I will
appreciate advises about two issues:
1) Widely speaking: Is such an approach correct? Can you
give me some references in the literature? If I have more
than one molecule (or even different molecular species)
in the cell a similar approach on more than one molecule
is still feasible, but is it worth while? How should I
model the neighbouring molecules' charge distribution
(Mulliken charges, charges fitted to the molecular
electrostatic potential, Atom-In-Molecule-derived
charges, orientable atomic dipoles, ... ) ?
2) More technically: do you know a program which reads the
crystalline structure (for example from the Cambridge
Database) and performs all coordinates manipulation I
will need ? In particular to obtain cartesian coordinates
of any specified molecule in the cell surrounded by all the
neighbouring molecules whose centers of mass are within
a certain radius from the reference molecule's center of
mass ?
Thank you in advance for all suggestions,
Giovanni.
----------------------------------------------------------------------
^^^ | SCALMANI Giovanni giovanni { *at * } sg2.csrsrc.mi.cnr.it
o o | Universita' degli Studi di Milano
| | Dipartimento di Chimica Fisica ed Elettrochimica
\_/ | via C.Golgi, 19 Phone: ++39-2-26603254
| 20133 Milano (Italy) Fax : ++39-2-70638129
----------------------------------------------------------------------
Similar Messages
01/07/1997: Electrostatic_effects_in_molecular_crystals
01/21/1997: Summary: Electrostatic effects in molecular crystals
02/21/1996: Summary: CRYSTAL & all
02/04/1997: Modeling Electrostatics - summary
10/24/1996: Charges
02/16/1997: Re: CCL:crystal packing calculations and programs
07/07/1995: Summary: Opinions on the quantum charges
11/22/1993: analyzing molecular systems
01/23/1998: SUMMARY: QEq charges & applications
06/10/1995: Conference in South Africa
Raw Message Text
|