From owner-chemistry %-% at %-% ccl.net Mon Mar  5 03:23:01 2007
From: "Ulrike Salzner salzner++fen.bilkent.edu.tr" <owner-chemistry::server.ccl.net>
To: CCL
Subject: CCL: NH4NO3 Structure
Message-Id: <-33729-070305021728-5341-6XIs3LqWxGf1ZimdIfkx+w::server.ccl.net>
X-Original-From: Ulrike Salzner <salzner- -fen.bilkent.edu.tr>
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Date: Mon, 05 Mar 2007 08:08:30 +0200
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Sent to CCL by: Ulrike Salzner [salzner _ fen.bilkent.edu.tr]
Dear Leh,
Supposing that you get NH3 and HNO3, I think the answer is that you are 
not dealing with a molecule but with an ionic system. Ionic systems are 
stable in a crystal due to the lattice energy or in  polar solvents as 
ion pairs. They are not stable in the gas phase and they dissociate 
homolyticly and not heterolyticly. This is what you have obtained. Just 
consider NaCl. The electron affinity of Cl is less than the ionization 
potential of sodium. Therfore electron transfer is unfavorable in the 
gas phase.
Regards,
Ulrike Salzner

Young Leh youngleh * gmail.com schrieb:
> Sent to CCL by: "Young  Leh" [youngleh*|*gmail.com]
> Dear CCLer,
>
> I have problem while optimizing the structure of NH4NO3.  It looks like no matter what my initial structure is, the structure always ends up with CH3 & HNO3.   Could somebody please provide me some help on this, a xyz or pdb file will greatly help?
>
> Thanks all
>
> Young Leh>
>
>
>
>
>