Subject: Summary of hydration of ions

From: "Prof. Shridhar R. Gadre" <[email-masked]>
Date: Wed, 15 Dec 1999 12:22:39 +0530

> From [email-masked]  Sun Nov 28 01:23:57 1999
I would be very grateful if you would kindly forward the replies you receive
and/or summarise.  I have always been interested in the differences of how
Phosphate and Sulfate bind to water, especiallly in view of the fact that
heparin is sulfated and the phosphate analog is inactive.
    I think H2O---X-
and other complexes have been calculated.  
Goutam Das
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> From [email-masked]  Sat Nov 27 23:45:33 1999
 Dear Prof. Gadre,
    One reference for hydration of F- is :
                 J. Chem. Phys. Vol 110, No. 9, 4338, 1999.
   By the way, as I told you I have developed a new supermolecule-continuum 
 solvation model. I want to send a pre-print of this paper to you. Could you
 kindly tell your postal address? Please give your comments after reading the
 paper.
 With best regards.
              Pradipta
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> From [email-masked]  Sun Nov 28 21:21:58 1999
Return-Path: <[email-masked]>
Status: R

You might check out some work by Sotiris Xantheas at EMSL/PNNL, Washington 
State, US. Also KS Sim ([email-masked]),
here are some references:

J. Baik et al, JCP, 110(18), p9116-9127 (1999)
  -  F- +Aqn n=1-6
RA Bryce et al, JPCA, 103, 4094-4100 (1999)
  - F- +Aq QM/MM
P. Weis et al, JACS, 3531-3532 (1999)
  - F- + Aq
C. Ebner et al,IJQC, 70, 877-886 (1998)
  - NO3 - + Aq
OM Cabarcos et al, JCP, 110(1) p5-8 (1999)
  - F- + Aqn n=3-5
SS Xantheas, JPC, 100, 9703-9713 (1996)
  - Cl- + Aqn n=1-4
Ayotte has done a lot of experimental work on these types of systems recently.
I have just published some work on lithium halide solutions in 
IJQC 76(1), and am preparing a paper on SO4 2- + Aq interactions, but 
this is probably tangential to what you are looking for.
-Cory
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Return-Path: <[email-masked]>

For what purpose? I have set up a couple of webpages for (H2O)8-10 but
those results haven't been published yet. I too have a couple of different
structures of (H2O)6,7. All are fully optimized and include analytical
frequencies at the HF/6-31G(d,p) level of theory.

If you are interested, please contact me.

Regards
Wolfgang Roth

===== http://www-public.rz.uni-duesseldorf.de/~rothw =====

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> From: Arshad Khan <[email-masked]>

A number of years ago I published a paper on smaller clusters (J. Phys. 
Chem. vol. 99, p12450, 1995).  

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> From: Richard A Caldwell <[email-masked]>

Our work is summarized in:

"Calculation of the Aqueous Solvation Free Energy of the Proton," with
Gregory J. Tawa, Igor Topol, R. A. Caldwell, A. Rashin, and S. K. Burt, J.
Chem. Phys,
1998, 109, 4852-4863.

Mostly our clusters were smaller that your targets.

R. A. CAldwell

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> From: [email-masked] (Bernd Hartke)
> 
You may want to check out our paper
   B.Hartke, M.Schuetz and H.-J.Werner, Chem.Phys. 239 (1998) 561
The corresponding ab-initio geometries (optimized at the LMP2 level with
aug-cc-pVDZ basis) can be downloaded from tc1.theochem.uni-stuttgart.de
by anonymous ftp: they reside in the directories "pub/severson/pentamer",
"pub/severson/hexamer" and "pub/severson/heptamer", in the files "*.xyz".
The corresponding energies are reported in the above paper (for the pentamer
and hexamer) and in the file "pub/severson/heptamer/Comments" (for the
heptamer), respectively.

As far as I know, there are no ab-initio optimized geometries for n>7 (Kim
et al. (Korea) is another good source, check out recent issues of JCP -- but
to my knowledge he also has not tried n>7 yet).
If you should find some, please tell me!

You may also want to check out the paper
   D.J.Wales and M.P.Hodges, Chem.Phys.Lett. 286 (1998) 65
for a large-scale global optimization of water clusters up to n=21
on the TIP4P potential -- in order to convince yourself that finding a
reasonable minimum structure for n=20 is a *formidable* task already on a
trivial empirical potential like TIP4P. Currently, with our own newly
developed global optimization strategies, we can go beyond n=21 on TIP4P,
but presumably not very far...

For this reason alone, I personally would not trust anybody who claims 
to have found the global minimum of
water_n for n=10 or larger by some fully ab-initio approach.

May I ask what your interest is in water clusters?

Kindest regards,
Bernd Hartke

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