DACP supposedly stands for "double azido cobalt perchlorate", the formula is trans-tetraamminediazido-cobalt(III) perchlorate [(NH3)4(N3-)2Co(3+)](ClO4-). What is interesting about this complex is the fact that it contains azide ligands, fuel and an oxidizer in a single compound.
It is briefly investigated in a freely available paper "Lead Azide Replacement Program NDIA Fuze Conference" by Bichay and Hirlinger. The compound is a powerful initiating explosive with properties comparable to BNCP (bis-nitrotetrazolate-cobalt-perchlorate) and has been proposed as replacement for both BNCP and lead azide.
A German paper "light absorption of azido-cobalt-ammines" is available in reference section and sheds more light on this family of complexes.
Experimental:
2,6ml 70% perchloric acid was neutralized with basic cobalt carbonate and filtered. Another 1ml of perchloric acid was neutralized with ammonia and the solutions combined. The resultung solution was a light magenta color .
In another beaker, 4g sodium azide was dissolved in 50ml water and 9ml 25% ammonia was added with stirring. The solutions where then combined. Complexation occured, as evidenced by deep blue coloration of the liquid.
A stream of air was then drawn through the solution for 3 hours. During this time the color changed from a deep blue to a lavender color. After standing for several hours, a microcrystalline powder had settled which was filtered and air dried.
There must be variation of this compound that is even better.
Perhaps hydrazine instead of ammonia? I would be hesitant to make a perchlorate complex hydrazine salt after reading about the accident with cobalt hydrazine perchlorate, which suggests dangerous friction sensitivity.
On January 7, 2010, Texas Tech University (TTU) graduate student Preston Brown was working to synthesize and characterize an energetic material, likely nickel hydrazine perchlorate, placed 5g into a mortar. He believed that the compound was safe when “wet,” so he added some hexane and—wearing safety goggles but without a blast shield—“very gently, very, very gently” used a pestle to try to break up the chunks, Brown told TTU environmental health and safety officers. He set down the mortar, then decided to give the compound one last stir. The mortar exploded causing severe injury.
It is not just complex salts, because hydroxylamine perchlorate is very sensitive (drop height 2cm). But hydrazinium nitroformate apparently is not very sensitive, as it has been researched as a solid rocket fuel oxidizer. But nitroformate probably has different compatibility issues than perchlorate. Ammonium nitroformate appears to be the most stable nitroformate salt.
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Silver nitroformate slowly decomposes at room temperature, and is a very sensitive explosive. The potassium salt, KC(NO2)3 is a lemon yellow crystalline solid that decomposes slowly at room temperatures and explodes above 95 °C. Ammonium nitroformate deflagrates or explodes above 200 °C. Hydrazinium nitroformate is thermally stable to above 125 °C. Most salts of trinitromethane derive from the aci-form. However, the silver and mercuric salts exist in two forms: colourless and yellow. This may indicate that two forms of these salts - nitro and aci - can exist.
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So it would seem nitroformate would be stable in the presence of hydrazine, but not with certain metals (probably including copper).
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Adding tetraamminecopper(II) nitrate powder to aq. sodium azotetrazole under stirring affords a bright green solid which is uncomparably mechanically far less sensitive than the extremely sensitive copper azotetrazole, but also less brisant.
Formatik
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I would have been a little concerned about whether nitroformate would be ligand towards Co+3, as this could result in dangerous sensitivity (nitroformate is stabilized by being an anion). But apparently complexed ammonia molecules make the transition metal ion less "noble" in character. (difficult to explain, hopefully you understand what I mean)
Nitroformate salts are usually bright yellow in color, but might not contribute a any color if the nitroformate acts as a ligand rather than anion, which would also presumably make it more sensitive.
Perhaps...
Hydrazine-diazido-cobalt nitroformate ?
(N2H4)2(N3)2Co[+] C(NO2)3[-]
Not sure what color it would be, but probably would have a grayish tone from being a mix of yellow and light purple. But difficult to speculate, as complex cobalt salts can take a range of colors.
A quick note about the chemistry of cobalt, solutions of Cobalt(II) salts in water are not oxidized chlorine, but the presence of ammonia renders the cobalt much more vulnerable to oxidation, even by air.
It might actually be fairly complicated to prepare a hydrazine cobalt(III) salt, since non-complexed cobalt(III) salts generally do not exist. Oxidizing the cobalt(II) with hydrazine already in the solution would also likely lead to oxidation of the hydrazine. Perhaps Co2O3 reacted with a solution of hydrazinium nitroformate, hydrazinium azide, and some additional hydrazoic acid would work.
Here is what the decomposition formula for the compound would be:
(N2H4)2[N3]2Co[C(NO2)3] --> CoO + 4 H2O + CO2 + 6½ N2
