>Dear all,
>
>We have tried to investigate the protonation energies of Adenine with ADF and
>encountered a small, but yet annoying problem. We have obtained values, that
>are about 280 kcal/mole higher than results in G98 and gas phase
>measurements. These two are in line.
>My question is, how do I calculate the protonation energy properly?
>

First of all, how did you calculate this energy ?
I assume with ADF99 ?

Did you just take the difference in total bonding energies ?

-- 
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drs. Marcel Swart
Theoretical Chemistry (MSC)
Molecular Dynamics (GBB)
Rijksuniversiteit Groningen
Chemistry Department
Nijenborgh 4
9747 AG Groningen
The Netherlands
tel : +31 - (0)50 - 3634377
fax : +31 - (0)50 - 3634441
E-mail : m.swart_at_chem.rug.nl
WWW: http://theochem.chem.rug.nl/~marcel/
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