Subject: CCL:SUMM: AM1 Proton Affinities

From: "Shoba.Ranganathan" <[email-masked]>
Date: Thu, 23 Jan 1997 11:42:28 +0000

I am posting an abbreviated version of the replies to my query, and
with names and e.mail addresses:

> Does anyone have a reference for AM1 or semi-empirical proton
> affinity calculations?

I am very grateful to all those who responded.

Shoba
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J. L. Ozment and A. M. Schmiedekamp, International J. Quant. Chem. 43,
783-800 (1992).

From: [email-masked]

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and the same reference with the following comment:

They concluded that AM1 is able to predict the relative PA's,
while the results of PM3 scatters.

Kazuo Teraishi ([email-masked])
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I have found 2 references particularly helpful in choosing a method.

 J. Ozment & A. Schmiedekamp, Int. J. Quant. Chem., 43, 783-800 (1992)

compares the accuracy of MNDO, AM1, and PM3 calculations of some 110
proton affinities, and

 Fitzgerald & Andzelm, J. Phys. Chem., 95, 10531-4 (1991)

compares DFT methods with MP2 calculations of 12 proton affinities.

Ernest Chamot ([email-masked])
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Here is a reference of AM1 calculated Proton Affinities:

       M.J.S. Dewar, K.M. Dieter, J. Am. Chem. Soc. 1986,108, 8075.

This reference is slightly old, but hope would serve the purpose.

Bishwajit ([email-masked])
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I have published on proton affinities in Group 14 elements (using PM3
to generate the numbers) in

J. Mol. Struct. (THEOCHEM) 338 (1995) 51-70.

Daniel J. Berger ([email-masked])
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I would like to point out my own paper.

"The role of amphotericin B amino group basicity in its antifungal
action. A theoretical approach" M.Baginski, P.Gariboldi, E.Borowski
Biophys.Chem. 49 (1994) 241-250

You may check it since we did some calculations of proton affinity by
AM1 and MNDO methods for models of amphotericin B derivatives but also
for 25 simple organic molecules (organic amines). We have found the
correlation between calcualted and experimantal values of PA for these
25 compounds. We also site other papers concerning this subject.

Maciej Baginski  ([email-masked])
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Have a look at Dewar & Dieter, JACS 1986, 108, 8075

Benzion Fuchs ([email-masked] or [email-masked])
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I have one reference concerning the use of MNDO and AM1 for the
prediction of proton affinities of aza-arenes:

J.F.Sanz, J. Anguino, J.Vilarrasa: J. Comput. Chem. 9, 784 (1988)

Another one, by myself, deals with the application of semiempirical
effective electronic potentials:

J.Spanget-Larsen: "Structure-reactivity correlations for aza-arenes.
Proton affinities, pKa values, hydrogen-deuterium exchange rates and
radical-induced C13 shifts", J. Phys. Org. Chem. 8, 496-505 (1995).

JENS SPANGET-LARSEN  ([email-masked])
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For AM1 you should look at
   M.J.S.Dewar and K.M.Dieter, JACS, 108, 8075 (1985),
for PM3 i would suggest our own article
   P.Burk, K.Herodes, I. Koppel and I. Koppel, Int.J.Quantum Chem.:
   Quantum Chem.Symp. 27,633 (1993)

Peeter Burk ([email-masked])
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You may had better refer the reference listed below.

1)Dewar, M. J. S.; Dieter, K. M. J. Am. Chem. Soc., 108, 8075(1986).
2)Taft, R.W.; Racynskay, E.D.; Maria, P.-C.;Leito, I.; Gal. J.-F.;
Decouzon, M.; Drapala, T.; Anvia, F. Pol. J. Chem. 1995,59,41.

KANZAKI KOJI ([email-masked])

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Do you know the article of S.J.Dixon et al. on the estimation of pK
using calculated atomic charges, in J.Comput.Chem. vol14, 1460 (1993)?

   Dr Tamas E. Gunda ([email-masked])
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