From owner-chemistry-: at :-ccl.net Tue May  9 05:49:00 2006
From: "Marcin Krol mykrol-.-cyf-kr.edu.pl" <owner-chemistry(~)server.ccl.net>
To: CCL
Subject: CCL:G: Calculation of pka
Message-Id: <-31714-060509054751-9414-ZybRhjhzkf1PcfbBeBGiIw(~)server.ccl.net>
X-Original-From: Marcin Krol <mykrol(a)cyf-kr.edu.pl>
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Date: Tue, 9 May 2006 11:47:41 +0200 (METDST)
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Sent to CCL by: Marcin Krol [mykrol(_)cyf-kr.edu.pl]
Hi,
It depends on how accurately you want to calculate pKa and how much time
you want to spend doing it. You can either use a
free pKa calculator such as Sparc - http://ibmlc2.chem.uga.edu/sparc/
very quick, but probably accuracy depends on your molecule belonging to
the test set. Check their reference, I can't open it.
Or you can go the tedious way and calculate it from
first principles (eg in gaussian, see eg. Liptak etal. JACS 2002
124:6421, Gao etal. JPCA 2005 109:10776), but you are also not guaranteed
to get good results (my own experience).
Hope this helps
marcin

> Sent to CCL by: kevin abbot [kevanabbot=-=yahoo.com]
>
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> Hi folks,
>   My question is really simple: are there some programs (free of charge)
> that permit to calculate pka of a determinated compound?
>
>   Any help is appreciated
>
>   Kevin