For professionals engaged in chemical research and development, a deep understanding of compound properties is fundamental. Nitrogen Triiodide, identified by CAS number 13444-85-4, is a compound that stands out not for its broad industrial applicability, but for its fascinating and volatile chemical behavior. This article explores the intrinsic chemistry of Nitrogen Triiodide, focusing on its properties and reactions, offering valuable insights for those looking to buy or work with this unique substance.

Molecular Structure and Properties of Nitrogen Triiodide

Nitrogen Triiodide, with the chemical formula NI3, is an inorganic compound typically appearing as unstable black crystals. Its structure is pyramidal, similar to ammonia and other nitrogen trihalides. The high degree of instability and explosiveness are attributed to the significant steric strain exerted by the three large iodine atoms packed around the central, much smaller nitrogen atom. This strain leads to a very low activation energy for decomposition, a process further driven by the exceptional thermodynamic stability of diatomic nitrogen (N2).

Key physical and chemical properties include:

  • Molar Mass: Approximately 394.72 g/mol.
  • Appearance: Black crystals, described as unstable.
  • Sensitivity: Extremely sensitive to touch, shock, friction, and heat when dry, acting as a primary contact explosive.
  • Decomposition: Rapidly decomposes when disturbed in its dry state.

Understanding the Explosive Nature and Decomposition

The explosive characteristic of Nitrogen Triiodide is its most defining feature. When in its dry form, the slightest perturbation can trigger a violent decomposition. The primary decomposition reaction is:

2 NI3(s) → N2(g) + 3 I2(g)

This reaction is highly exothermic. The resulting gaseous products are nitrogen and iodine vapor, which manifests as a distinctive purple cloud. The process is so sensitive that it can even be initiated by alpha radiation.

When NI3 is prepared from ammonia and iodine, it often forms an adduct, NI3·NH3. This adduct, while also unstable, decomposes differently:

8 NI3·NH3 → 5 N2 + 6 NH4I + 9 I2

The orange-to-purple stains left by the iodine vapor after detonation can be removed using a sodium thiosulfate solution.

Sourcing and Application Considerations

For B2B buyers interested in Nitrogen Triiodide (CAS 13444-85-4), understanding these chemical properties is vital for safe procurement and use. While its explosive nature makes it unsuitable for bulk industrial applications, it is a valuable compound for laboratory demonstrations or research into energetic materials. When you buy Nitrogen Triiodide, always ensure you are sourcing from a reputable manufacturer in China that provides detailed handling instructions and safety data.

Engaging with suppliers who can offer technical support regarding the properties and reactions of NI3 will ensure you use this compound responsibly and effectively in your research or educational context. Always consult the Safety Data Sheet (SDS) before any handling or experimental procedure.