Nitrogen iodide

Jod-saure, /, iodic acid, -schwefel, m. sulfur iodide, -serum, n. iodized serum, -silber, n. silver iodide, -silizium, n. silicon iodide. -stSrke, /. starch iodide, iodized starch. -stSrkepapier, n. starch iodide paper, -stick-stoff, m. nitrogen iodide, -thymol, n.iPhaTm.) thymol iodide, -tinktur,/. tincture of iodine, -toluol, n. iodotoluene. -iibertrilger, m. iodine carrier. 

Engelhardt, Coordination Problems of Nitrogen-Iodide Compounds in Liquid Ammonia in ProcSthlntConfCoordChem, Springer, Vienna... 

The only explosive iodide is Nitrogen Iodide which is described below. 

Nitrogen Iodide (also known as Nitrogen Triiodide). NI3 mw 394.77, N 3.55% black cryst, explodes on heating, sublimes in vac, insol in w, decomp in hot water (Ref 15). Prepd by treating I2 with coned aq NH3, probably via... 

Nitrogen Iodide is.an exceedingly sensitive explosive when dry. It explodes upon the slightest touch and also upon very mild heating such as in a warm air stream. It must be stored wet, preferably under ether (Ref 15). Because of its phenomenal sensitivity NI3 is not a practical explosive, but by the same token it has been studied rather extensively to determine why it is so sensitive. Since these studies contribute to the understanding of explosion phenomena they are described below... 

Nitrogen iodide (NI3.NH3) is a very unstable material and will explode under the action of very weak shocks. Even at liquid air temperatures, initiation occurs at an energy of 0.6g/cm (Ref 4). The stability of nitrogen iodide under normal conditions depends to a great extent on the presence of ammonia which retards the decomposition of the pure NI3 (Ref 8). 

Meerkamper (Ref 9). has found that the sensitivity to impact is also reduced in an ammonia atmosphere. Presumably the ammonia is rapidly adsorbed on the freshly exposed surface of the crystals of nitrogen iodide and. prevents the decomposition from spreading ... 

Nitrogen Iodide NI3.NH3 car. also be decomposed and ignited by light (Refs 10 ... 

Meerkamper (Ref 9) irradiated nitrogen iodide in low-pressure atmospheres of air or ammonia at various temperatures and determined the quantum yield of the decomposition. He finds that this value is not constant but increases to a limiting value as the irradiation is continued. 

This limiting value depends on the ambient temperature. The results suggest that the decomposition is mainly thermal due to the conversion of the light energy into heat. There is a small (5 to 10%) photochemical effect particularly when the nitrogen iodide is irradiated with blue or red light... 

Figure. Relation between the light energy required for ignition (joule) and temperature (°C) for nitrogen iodide (Ref 9)...

If a tube filled with Xenon is used instead of the spark in air the explosion begins 3.7 jusec after the first appearance of light. This value of 3.7 /usee means that ignition takes place ca 0.5 jusec after the flash has reached its maximum intensity. Again it is clear that only a small part of the incident light is used for igniting the nitrogen iodide... 

Nitrogen iodide cannot be ignited under concentrated ammonia solutions even with a very strong flash. Under pure water local explosions... 

Poole has ignited Nitrogen Iodide by a single a-particle from a radium source (Refs 5 14)... 

Nitrogen iodide will explode when heated in air at 50°C. The equation representing the decomposition is (Ref 4)... 

Garner Latchem (Ref 6) found that when nitrogen iodide (NI3 -NH3) is dried over a layer of P2Os at a pressure of 2 x 10 3cm Hg, thermal decomposition could be studied at temperatures below 0°C. However, when the pressure fell below 2 x 10-3cm Hg, explosion of the nitrogen iodide took place at temperatures as low as -11°C. At low pressures Meldrum (Refs 7 9) has shown that the equation representing the decomposition is different from that given above,... 

Ammonia and water vapor retard the decomposition of the nitrogen iodide, a pressure of 10"3 cm Hg of ammonia being sufficient to stop the reaction... 

It is clear from the results described above that the presence of ammonia can under certain conditions prevent the explosion of nitrogen iodide when the decomposition is brought about by heat, light, shock, or ionizing radiation... 

Schrankler (Ref 2) claim that Mercuric Fulminate, Azides even TNT were initiated by the action of H, Ar Hg ions. This was not substantiated (Ref 3). Nitrogen Iodide is definitely initiated by a-particles (Refs 1 ... 

Cd azides, Ag acetylide and nitrogen iodide) by electrons, neutrons, fusion products and X-rays. All these substances were exploded by an intense electron stream but it was shown that this was due to a thermal effect. Fission products exploded nitrogen iodide but in the other substances some changes within the crystals took place but no explosions. The experiments showed that, in general, the activation of a small group of adjacent molecules was not enough to cause explosion... 

Also see articles on Initiation and on Nitrogen Iodide (under Iodides) in this Vol Refs 1) F.P. Bowden K. Singh, PrRoyS A227, 23-30 33-5 (1954) CA 49, 4991 (1955) 2) Bowden Yoffe (1958) Chapt VII... 

In one of J. S. Stas processes, the iodine was dissolved in a soln. of potassium iodide. The soln. was diluted with water until a precipitate began to form, and then three-fourths of the amount of water required to precipitate all the iodine were added. The separated iodine was washed free from potassium iodide by decantation, the crystals, after draining, were dried over calcium nitrate in vacuo, and then distilled twice from barium oxide. In another process, J. S. Stas purified the iodine by first treating the iodide with ammonia which converts about 95 per cent, of it into the explosive nitrogen iodide. The washed nitrogen iodide decomposes quietly when warmed with an excess of water. J. S. Stas thus describes the procedure ... 

Ammonium iodate, NH4IO3.—This salt is formed by H. Kammerer68 as a sparingly soluble white crystalline powder by the neutralisation of aq. iodic acid, or iodine trichloride with ammonia or ammonium carbonate from iodine water and ammonia from cold soln. of ammonium carbonate and barium iodate. A. Guyard, and F. D. Chattaway and K. J. P. Orton, also noticed that when nitrogen iodide is suspended in aqua ammonia and exposed to sunlight, ammonium iodide and iodate are formed. 

When treated with water, bromine and iodine are set free hydrochloric acid liberates iodine sodium or ammonium hydroxides give a black precipitate of nitrogen iodide, and the mother liquid liberates bromine when treated with hydrochloric acid. Sulphurous acid gives hydrobromic and hydriodic acids. F. Ephraim. found the dissociation press, of NI IB to be 65 mm. at 107° 204 mm. at 134° 465 mm. at 154° and 640 mm. at 161°. 

Meidrum (Ref 4 studied the thermal de-compn of nitrogen iodide at low pressure and showed the reaction to be ... 

Alpha-Compounds, such as a-Mononitronaphtha-lene, a-Trinitrotoluene, etc are listed under the corresponding parent compels, such as Naphthalene, Toluene etc Alpha Particles as Initiators of Detonation, According to some investigators a-particles emitted by radium or other sources can, by irradiation, initiate the detonation of very sensitive expls, such as nitrogen iodide, but not of expls such as acerylides or azides. Nitrogen iodide can also be irradiated by fission products (See also Initiation of Explosives by Irradiation)... 

Ammoniaeal Nitrogen Iodide. See under Nitrogen Iodide... 

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