Swany
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Nitronium ion, Dinitrogen Pentoxide
Well, this could perhaps be in several different sections. General Chem seems appropriate. I'll let the mods decide that.
Since mixed acid nitrating agents (HNO3/H2SO4) are falling out of favor with industry due to the lack of selectivity, incompatibility with N-nitro
compounds, contamination of products, and general disposial issues, nitrating agents based on N2O5/HNO3 and N2O5/chlorinated organic solvent are
becoming more and more popular. They nitrate very quickly, waste products are more manageble, there is no incompatibility with strained cyclic N-nitro
compounds, and in theory one can create the former with air, water and electricity.
Now skipping around to N2O5. Dinitrogen pentoxide is solid at RT, but sublimes at 32.4 degrees C. It is molecular in its gaseous and liquid forms, and
below -70 degrees C it is also in a metastable molecular form, with both N atoms being in the +5 oxidation state. Above that temp, it converts
exothermically to the ionic form of NO2NO3; nitronium nitrate. In chlorinated organic solvents, it is in a molecular form, though dissolved in HNO3 I
belive it forms ions. At room temp it has a half-life of about 9 hours, 0 degrees C is about 2 weeks, and -60 is about a year.
Can anyone think of any research projects I could do regarding the nitronium ion or dinitrogen pentoxide? I was thinking about somehow comparing the
stability of the molecular and ionic forms, or somehow making it more stable... but quite frankly anything would be interesting. I will edit this post
later with some references and more information, but I have to be going now.
Thanks for your time.
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chemoleo
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I suggest you have a look at the research at Thomas Klapoetcke (spelling might be wrong) who works at the TU Munich. This group works on EM research,
and they synthesised a variety of energetic compounds that are quite exotic, to say the least. I am sure I seem to remember unusual synthesis
techniques using N2O5 or other derivatives. Searching PEP would be useful for starters.
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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The_Davster
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You could do the project on high oxidation state oxides, like N2O5, I2O5, Mn2O7, they all can be considered ionic. I2O5 even behaves kinda like N2O5,
it substitutes benzene rings in a similar way. But that is getting away from your origional idea.
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JohnWW
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The mechanism of nitration of organic compounds involves electrophilic attack by the nitronium, NO2+, cation, which can exist only in concentrated
solutions containing pentavalent N (e.g. HNO3) plus a mineral acid stronger than HNO3. As well as solid N2O5 being nitronium nitrate, it exists as,
and can be isolated as, (NO2)2SO4, NO2ClO4, NO2BrO4, NO2PF6, NO2AsF6, NO2SbF6, which can also be used for nitration in suitable solvents.
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maxidastier
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As this was the only existing thread regarding N2O5, I will post my request here:
I'm looking for the Full text PDF of "Plasma-assisted synthesis of N2O5 from NO2 in air at atmospheric pressure"
from http://iopscience.iop.org/0022-3727/32/10/310
[Edited on 1-4-2011 by maxidastier]
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blogfast25
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Mn2O7 is definitely NOT considered ionic. An oily, liquid substance at RT, structurally this is confirmed more covalent than ionic. Or so says Wiki...
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physics inclination
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here's the link to the sci-hub copy of the article, if anyone's still interested in N2O5 (sorry I keep reviving years-old threads lol)
https://sci-hub.ac/10.1088/0022-3727/32/10/310
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