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>I have a little experience with nitrogen triiodide, having made some a
>few years ago.  I had heard that it is very sensitive, so I was very 
>careful.  Good thing.
>I left the product outside (it was summer) to dry overnight.  The com-
>pound was in an open, light plastic weighing dish, sitting on a table.
>The stuff detonated in the middle of the night.  I think that either
>the wind blew the dish off the table or an unfortunate bug landed on it.
>In either case, once the compound dried, it didn't take much to set the
>stuff off.  When wet the stuff seems pretty stable, but I wouldn't trust
>Nitrogen triiodide seems to be too unstable for anything but tiny dem-
>onstration purposes.

Between the ages of 12 and 18 I made countless batches at home. 
It is safe and can be stored for long periods (months) as long as one uses
plenty of ammonia, washes it well, and keeps it wet. 

In the beginning I would take small vials of it with me (friends, school, etc).
Scatter small dabs in places were it would remain undisturbed long enough
to dry.  Sometimes part of it would dry, revert (explode), and scatter may
still wet particles all over.  It's causes a lot of excitment when it gets
in peoples clothes, hair, etc.  (Usually mine.) 

When I made a large batch I learned that it can be unstable when wet.
In a later, small experiment, I verified that not using enough ammonia
causes it to be unstable when wet.

The largest batch I ever made exploded while I was spreading the wet paste
in a glass funnel over a beaker as it was drying.  I was very lucky to not
get cut by the flying glass.  The explosion released much iodine gas.  My
hand made a good place for it to crystalize.  It took many washings with
alcohol, water, and soap, to remove.  After this I continued to make large
amounts, but I was a lot more careful.

From: (Doug Gwyn)

>Hello.  I have a couple of questions.  First, after about 45
>minutes of drying, the mixture of Iodine crystal and Ammonia will
>ignite on its own and I was wondering what the cause might be.

This is to be expected.  Wash the final NI3 in alcohol and keep it damp
until you have applied it to the surfaces that you want to booby-trap.

I think I'll throw my $0.02 on this one.  First of all, I'm an organic
chemist with a fondness for molecular orbital studies in both inorganic
and organic chemistry.  I think I can place your level of study in the
field so I'll try to keep the explanation there and not get too involved.

First, I want to EMPHASIZE that this is not the kind of compound that you
want to approach the way you are.  For one thing, one could say that the 
reaction liberates a fair amount of energy, but I doubt whether anybody
has measured the thermal output output of the decomposition rxn.  For one
thing, this compound is pretty much a sound and fury compound and you
can't use it as a bulk explosive.  When dry, if so much as a fly lands on
the stuff, it will detonate, hence it's use as a convienent "boobytrap"
compound ( I can hear the gears in your head spinning allready ).

Ok, 1) it's molecular formula is NI3 (Nitrogen Triiodide), but the
compound hangs around with a molecule of ammonia hence it is also 
represented as NH3*NI3.  One of the driving forces of the decomposition]
rxn and the reason for the compounds instability is the relative size of
the atoms invloved.  Big ol' Iodine bonded to little ol' Nitrogen.  
Knowing the chemical formula, it's no major feat to figure on the rxn
products being N2 gas and, because of the energy being released, I2 gas.

I've allready commented on the nature of the decomp rxn so I'll move on
to the prep procedure.  You better take note because it's so simple that
it is really easy to skip a lot of safety measures and will get you in a 
lot of trouble.

The only two reagents are 15 molar (15M) ammonia water and Iodine (I2) 
crystals.  Maybe somebody can share their experience ( success or failure )
with salvaging I2 crystals from Tincture of Iodine or other readily available
source of raw Iodine as I2 crystals really are expensive.  The reaction is 
pretty simple if you use 15M ammonia as its pretty difficult to deplete the
rxn mixture of ammonia at that stength.  You just add the I2 crystals to the
ammonia and swirl it a few moments and, presto, you have NI3.  You better not
stop reading now because you'll save yourself a lot of embarrasment and injury
if you take the additional safety measures I mention.

Ok. Now that you have the stuff, you need to realize that I is inherently
unstable for the reasons that I cited above and it should only be stored for
a couple of days max.  I personally just whip up what I need, stabilize it,
set my trap and clean up the mess.  Please don't go throwing I2 down the
drain and don't throw it in the trash as it's a reasonably bad safety hazard.
You'll probably pay a pretty penny for the crystals so just use what you 
need and store the rest in a COOL, DRY, DARK location.  You need to have
filter paper, a mini spatula ( 4-8mm wide ), some ether preferably but
alcohol also works and a small storage container ( a shallow one will be 
more convienent than something deep like a test tube ).  Filter the rxn
mixture though the filter paper and put the black crystals under the ether.
You can crush the I2 crystals while their in ammonia to increase your yield
and produce finer NI3 cystals that are easier to apply underneath surfaces
as it will produce more of a paste than individual crystals when it is stored
under the ether.  The tradeoff is that every crystal you make will explode
when it drys and you will find your hand brushing your work surface only to 
find a protracted popping as you hand trips off the thousands of crystals
that fall as a result of dripping, spilling and/or dropping various stages
of the rxn.  This can be more of an annoyance than anything but careful
technique reflects a respect for what you are making and will payoff in the
end.  As long as the NI3 is stored under ether it's safe.  Don't leave the 
lid off your storage container as both ether and alcohol ( I mean the PURE
stuff, 95 percent or better ) evaporate pretty fast and, since adding ether
to a dry pile of NI3 MIGHT set the whole batch off, you'll loose you're
whole batch.  I said that this compound can only be stored a couple of days
max if you need to but it will slowly decompose into N2 and I2 so take that
into account when you seal your storage container.  If your storage container
breaks due to a pressure buildup, 1) you made too much, 2) it won't detonate
the NI3 in the container 3) the NI3 will detonate itself as soon as it is 
dried and you disturb it.  If a major spill of NI3 occurrs at anytime, the 
best thing to do is to distribute it as widely as possible with water.  Don't
use your ether or alcohol as it won't have any added benefit and will only
create a MAJOR big time fire hazard.

In closing, NI3 is a low impulse explosive which means its all sound and flash
but won't blow hole in plate steel.  A sheet of paper is readily dispatched
though and I've never though of it but it might have some small use in
insect control if you like handling bugs.  Just apply it to a STABLE ( no
vibrations or movement ) surface and it should dry in 5-10 minutes depending
on the quality of your storage medium.  Once dry, any contact or vibration
will set it off and it basically sounds like one of those snap-and-pop
things you can buy at novelty stores.  This of course depends on how much
you use, which is my final point.  I once scared a lab assistant out of his
skin buy applying a line of the stuff about 1 inch long, 0.25 inches wide and
an 0.125 inches high to the roller surface on his desk drawer and left the
drawer open. Yes, he closed it.  Yes, he thought he had been shot. Be careful
with this stuff and I will be glad to tell you anything else you want to know
about it.  Just send e-mail to  This stuff can be really fun
without getting out of hand if your just careful with it.

A slightly less volatile version can be made of it if you can't get the
chemicals.  Use household ammonia and tincture of iodine.
Mix together with excess ammonia and filter. You should have a black sludge
left in the filter paper. If the filtrate is brown then you didn't add enough
ammonia, this will still work, but it's just a waste of iodine. Dry it out as 
soon as possible, otherwise it tends to dissolve back into the solution.
Infact it took me a few attempts to manage this, first time I just let the 
precipotate float to the bottom, but it dissappeared after an hour.
So filter it as soon as you can.

From what everybody else has been saying, this is a little more stable,
obviously because it is not so pure, however, ONLY MAKE IT IN SMALL QUANTITES.
I normally only make about the volume of a little finger nail. IT DON'T

From: larry@kitty.UUCP (Larry Lippman)

In article <27674@sequent.UUCP>, rjk@sequent.UUCP (Robert Kelley) writes:
> We balanced the stoichiometry by noting a color change
> from reddish-brown to grayish-green.  Is that sound?


> Also, it seems that there may have been two different crystalline products
> produced, and perhaps a gas evolved.
> Where can I read about this?

        On the Net, of course. :-)

        Depending upon the stochiometry, temperature and pressure, more
than one product may result from the reaction between iodine and ammonium
hydroxide (aqueous ammonia).

        At slightly above 20 deg C, with the proper stochiometry, the
reaction will produce nitrogen triiodide 1-ammonate (NI3.NH3)n, which are
black crystals comprised of zigzag chains of NI3 tetrahedra, with NH3
molecules lying between these chains and *linking them together*.  This
configuration is known as an "ammonate".

        At temperatures higher than 20 deg C, the above reaction will
produce nitrogen triodide 3-ammonate (NI3.3NH3)n.

        Nitrogen triiodide n-ammonates where n is higher than 3 have
been identified.

        The nitrogen triiodide ammonates are NOT stable in water, and
readily undergo hydrolysis.  Under relatively neutral pH comditions,
nitrogen triiodide ammonates undergo hydrolysis to form hydrogen iodide
(HI) and nitrogen (III) trioxide (N2O3).  Under alkaline pH conditions,
such hydrolysis yields ammonium hypoiodite and ammonia.  Note that
the above hydrolysis produces gaseous products.

        I can assure Net readers that the internal structures of the
nitrogen triiodide n-ammonates have been well studied using x-ray
crystallography, although the results may not be in the literature.
I helped a fellow PhD candidate conduct such a study somewhat over
20 years ago.  Since we both had the same thesis adviser, who was not
known for either sense of humor or "adventuresome spirit", and since
our efforts placed some rather expensive analytical apparatus at some
considerable risk, we elected not to publish the results. :-)

From: (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: Ammonium Triiodine stabilization
Date: 11 Jul 1995 07:58:12 GMT
Organization: Consulting Chemist

In article <3tsuh5$ard@odo.PEAK.ORG>, billn@PEAK.ORG (Bill Nelson) says:

>It is possible that the common method of producing the substance produces
>NI3 - and that NI3.NH3 is only directly produced by passing gaseous NH3 over

Maybe I can help this discussion a bit>

The nitrogen triiodide which is of such great interest to the
teenybombers is NI3:XNH3 where X can be any number between 1
and twelve depending on the temperature at which it is prepared.
As one might expect, the material contains less ammonia when 
made at higher temperatures or when allowed to evaporate off
some ammonia. It never reaches the straight NI3 state, but
can get to NI3:NH3 which is the approximate composition that 
goes boom so very easily.

Now a non-explosive topic:

The iodide ion (I-) readily attaches itself to an iodine molecule
to give the stable I3- (triodide) anion which has nothing to do
with NI3 in which the iodine atoms are attached to the nitrogen
atom and not to one another. Only the name "triodide" is the 
same; the properties are much different.

When you buy colorless iodine tincture for cuts, what you get is 
a solution of potassium or sodium triodide (KI3 or NaI3). The 
ammonium salt (NH4NI3) is also modestly stable, so there is such 
a thing as ammonium triodide, but it is not an explosive 

BTW I have not seen it mentioned in this forum, but it may be
of interest to note that NI3:NH3 explodes spontaneously at 
temperatures of about 32 deg F or more.  If dabs of the material
are placed on a sheet of plywood facing even a Seattle sun, they
will explode at random intervals as the temperature of the 
surface rises a bit above the magic temperature.


From: (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: Ammonium Triiodine stabilization
Date: 12 Jul 1995 03:59:02 GMT
Organization: Consulting Chemist

In article <3ttauk$>, (Gerald L. 
Hurst) says:

>BTW I have not seen it mentioned in this forum, but it may be
>of interest to note that NI3:NH3 explodes spontaneously at 
>temperatures of about 32 deg F or more.  If dabs of the material
>are placed on a sheet of plywood facing even a Seattle sun, they
>will explode at random intervals as the temperature of the 
>surface rises a bit above the magic temperature.

Sorry about that, guys. I meant to say that NI3:NH3 autodetonates
above 32 deg C not F. It is obviously stable (more or less) at
room temperature, but it goes off at slightly higher temperatures,
i.e. in the summer sun.


From: (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: Ammonium Triiodine stabilization
Date: 13 Jul 1995 04:44:56 GMT
Organization: Consulting Chemist
Lines: 43

In article <>, 
Steve Roys <> says:

>On 12 Jul 1995, Gerald L. Hurst wrote:
>> Sorry about that, guys. I meant to say that NI3:NH3 autodetonates
>> above 32 deg C not F. It is obviously stable (more or less) at
>> room temperature, but it goes off at slightly higher temperatures,
>> i.e. in the summer sun.
>DEFINATELY NOT TRUE!  I have had NI3:NH3 explode under water in the 
>refrigerator.  The stuff is NOT STABLE (except possibly at cryogenic 
>temperatures?) and will detonate if you look at it cross-eyed, hot or 
>cold, dry or wet!

You have to read the second sentence in the context of the first one
in order to understand the meaning. Of course NI3:NH3 is not stable
in the absolute sense. For Pete's sake it is an explosive.

The substance is stable with respect to AUTODETONATION (usually and
in small quantities). This does not mean it will not explode if it
is caressed by the breeze from a butterfly wing.

Let me spell out the experiment:

Two dozen dabs of wet freshly prepared ammoniacal NI3:XNH3 were
applied to a 4X8 sheet of quarter-inch plywood and allowed to dry 
at an ambient temperature below 20 deg C. The sheet was placed 
facing the sun on a cool Seattle spring day. As the surface 
temperature very slowly passed through approximately 32 deg C, 
the spots exploded randomly and independently with no spot to spot 
propagation over a period of about 30 minutes.

The material was initiated not by the direct photolytic effect of 
solar radiation, but by the rise in temperature. I know this 
because I was studying the possibility of using light initiated
explosives for some spook application at the time, and I was merely
verifying data I had read which indicated that the autodetonation
temperature was in the 32 deg C range.  

More sayeth affiant not.


From: (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: Ammonium Tri-Iodide is for sissies
Date: 16 Jul 1995 01:47:32 GMT
Organization: Consulting Chemist
Lines: 26

In article
<>, "M.
Durller" <> says:

>On 14 Jul 1995 wrote:
>>  Ammonium Tri-Iodide?  Bah!  Now Potassium Tri-Iodide-that's an unstable
>> explosive for real men!
>>                       ;-)
>What does one do to make the explosive for real men?

Add iodine crystals to a solution of potassium iodide to make
colorless potassium triodide solution. Evaporate off the water
to recover the solid  material. 

KI + I2 -> KI3

The product is stable and not explosive, but it is a good antiseptic
and is sold as a tincture known as "colorless Iodine." Some people
claim that it is effective as a topical treatment for warts.  I have
observed the disappearance of warts after a couple of weeks of daily
treatment, but mention this only anecdotally.


From: (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: What is NitrogrenTriChloride?
Date: 8 Oct 1996 18:44:07 GMT

In article <>, Rob Porter
<> says:

>Close but not quite. It is ammonia and iodine that makes an explosive, 
>nitrogen triiodide. I have made this a number o times in my younger 
>years. You place iodine crystals in a filter cone and pour household 
>ammonia through it (I never used specific amounts). The resulting slurry 
>is non-explosive until dry, 


Don't bet your fingers and eyes that the slurry is non-explosive.  It
is less sensitive than the dry monoammoniate NI3:NH3 but not always, 
if ever, inert. NI3 apparently forms a series of adducts with ammonia.
During the drying process, both combined ammonia and free water are lost.
It is likely that low-ammonia wet NI3 is quite explosive and 
indistinguishable from wet and relatively less explosive high-ammonia 

Jerry (Ico)

From: (Gerald L. Hurst)
Newsgroups: sci.chem
Subject: Re: Nitrogen Iodide
Date: 2 Nov 1995 08:58:32 GMT
Organization: Consulting Chemist

In article <>, (JOSEPH S WARD) says:

>Is nitrogen iodide an explosive???   I know nitogen triiodide is an explosive
>I make it all the time for demostrations.

Ah, so you know about diiododiazine. The trans isomer, of course,
is the more stable form of INNI. The synthesis of the trans material
is best accomplished by removal of two iodine atoms from tetraiodo
hydrazine vapor at reduced temperature.

Of course, INNI is much less stable than NI3:NH3. As you know
the latter can be set of by a fly landing on it whereas INNI
detonates 50% of the time from single incidences of molecular
collision at room temperature by gaseous molecules. It is 
therefore necessary to store the material in a super high vacuum
on a seismometer foundation to prevent accidental detonation.


From: (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: Iodine Crystals (Touch Explosives)?'s
Date: 27 Jun 1996 21:06:04 GMT

In article <4qs5te$>,
(Thurston V) says:

>I have read over 5 different articles on how to make touch explosives and
>they are all different.
>Can someone tell me how to make iodine crystals with plain old iodine and
>then how to mix it with the ammonia

What do you mean by "plain old iodine"?  Iodine crystals are as "plain"
as iodine gets given that they consist of 100% elemental iodine.

The liquid you put on cuts is a tincture, i.e., a liquid solution of
iodine in a solvent.  The so-called "colorless iodine" is not iodine
at all, but is instead an alkali metal triodide salt, e.g, sodium
or potassium triodide, MI3. Complexing an iodine molecule (I2) with
the iodide ion (I-)may be looked at as a method of solubilizing the
iodine for use in water solutions.

We still call the metal triodide solution "iodine" for medical purposes
because it kills germs like iodine. Presumably the solution makes a low 
but suffucient concentration of elemental iodine available via the 

	I3(-) <--> I2 + I(-)

It follows that heating the solid residue from the evaporation of the
liquid would produce elemental iodine which could be condensed on
a cold surface.  Don't bother doing this other than for the joy of the
chemistry because there is not much iodine there and the cost would be
ridiculous unless you will be satisfied with a purple stain :)

More interesting would be to prepare iodine from seaweed by a scaled
down version of the old commercial process described in many elementary 
chemistry books.  This is actually a lot more interesting than making a 
dangerously sensitive "touch explosive" from iodine.  The latter is a 
pipsqueak among explosives but dangerously sensitive - just strong 
enough to cost you some fingers or eyes and worthless for both explosive
and pyrotechnic use.

Jerry (Ico)

From: (E. Michael Smith)
Newsgroups: rec.pyrotechnics
Subject: Re: Ammonium Tri-iodide
Message-ID: <>
Date: 21 Jan 93 00:16:26 GMT

In article <> (bill nelson) writes:
> (Alan Yasutovich) writes:
>: 	How does one make this ?
>Very carefully.
>See if you can find a copy of TBBOM. The directions there are fairly
>reasonable. Remember to make very small batches and follow all safety

My high school chemistry teacher made it once as a demonstration.
Put a filter paper in a funnel.  Added iodine crystals.  Dribbled
ammonium hydroxide over it.  Took the WET filter paper and opened
it flat on the window ledge, then started the lecture.  About 30
minutes into the lecture, he touched it with a meter stick.  BANG!
Everyone was 'suddenly interested' in his lecture topic ;-) reaction
kinetics ...

It CAN sometimes go off when wet, or one small spot can dry setting
off the rest.  BTW, 1/8 teaspoon of iodine is more than enough ...


E. Michael Smith  ems@apple.COM

'Whatever you can do, or dream you can, begin it.  Boldness has
 genius, power and magic in it.'  -  Goethe

I am not responsible nor is anyone else.  Everything is disclaimed.

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