Pentazenium tetraazidoborate is an extremely unstable

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

with the formula N₅ (N₃)₄ It is a white solid that violently explodes at room temperature. This compound has a 95.7%

nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...

content which is the highest known of a chemical compound, which exceeds even that of

ammonium azide Ammonium azide is the chemical compound with the formula , being the salt of ammonia and hydrazoic acid. Like other inorganic azides, this colourless crystalline salt is a powerful explosive, although it has a remarkably low sensitivity. is phys ...

(93.3%) and

1-diazidocarbamoyl-5-azidotetrazole 1-Diazidocarbamoyl-5-azidotetrazole, often jokingly referred to as azidoazide azide, is a heterocyclic inorganic compound with the formula C2N14. It is an extremely sensitive explosive. Synthesis 1-Diazidocarbamoyl-5-azidotetrazole was produced ...

(89.1%).

Production and properties

The production of N₅ (N₃)₄requires a multi-step synthesis, first,

hydrazoic acid Hydrazoic acid, also known as hydrogen azide or azoimide, This also contains a detailed description of the contemporaneous production process. is a compound with the chemical formula . It is a colorless, volatile, and explosive liquid at room tem ...

and

sodium borohydride Sodium borohydride, also known as sodium tetrahydridoborate and sodium tetrahydroborate, is an inorganic compound with the formula Na BH4. This white solid, usually encountered as an aqueous basic solution, is a reducing agent that finds appli ...

is reacted in

diethyl ether Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liq ...

at -78 °C to produce sodium tetraazidoborate (which decomposes at 76 °C): :NaBH₄ + 4HN₃ → Na (N₃)₄+ 4H₂ The other reactant, pentazenium hexafluoroantimonate, its produced by the reaction of N₂F⁺ and

antimony(V) fluoride Antimony pentafluoride is the inorganic compound with the formula Sb F5. This colourless, viscous liquid is a valuable Lewis acid and a component of the superacid fluoroantimonic acid, formed when mixing liquid HF with liquid SbF5 in a 2:1 ratio. ...

. Then, two reactants that are produced are mixed at -64 °C under

sulfur dioxide Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a toxic gas responsible for the odor of burnt matches. It is released naturally by volcanic activ ...

: :Na (N₃)₄+ N₅SbF₆ → N₅ (N₃)₄+ NaSbF₆ to produce the pentazenium tetraazidoborate. If heated, it decomposes into nitrogen gas and

boron triazide Boron triazide, also known as triazidoborane, is a thermally unstable compound of boron and nitrogen with a nitrogen content of 92.1 % (by the standard atomic weight). Formally, it is the triazido derivative of borane and is a covalent inorganic a ...

; the boron triazide further decomposes into

boron nitride Boron nitride is a thermally and chemically resistant refractory compound of boron and nitrogen with the chemical formula BN. It exists in various crystalline forms that are isoelectronic to a similarly structured carbon lattice. The hexagonal ...

and nitrogen. The overall reaction is the following: :N₅ (N₃)₄→ 8N₂ + BN The compound is extremely sensitive, an attempted

Raman spectroscopy Raman spectroscopy () (named after Indian physicist C. V. Raman) is a spectroscopic technique typically used to determine vibrational modes of molecules, although rotational and other low-frequency modes of systems may also be observed. Raman sp ...

of a 500 mg sample of the compound resulted in an explosion.

References

{{reflist Azido compounds