Copper Iodide

Copper(I) iodide, commonly known as Copper Iodide (CuI), is a white to light gray or tan crystalline powder (may appear reddish-brown due to impurities), used as a catalyst in organic synthesis and in cloud seeding applications.​

Identity and Composition

Chemical name: Copper(I) iodide; cuprous iodide.​

Molecular formula: CuI; molecular weight 190.45 g/mol.​

Grade specifications: Purum or analytical grades ≥98–99.9% purity, low impurities (e.g., sulfate ≤5000 ppm, Fe ≤50 ppm).​

Physical Properties

Appearance: White/light gray powder (tan/reddish with impurities).​

Density: 5.62–5.67 g/cm³.​

Melting point: 605–606 °C; boiling point ~1290–2354 °F.​

Solubility: Poorly soluble in water; soluble in ammonia, KI solutions, acetonitrile; polymorphic (zinc blende γ-form at RT).​

Typical Uses

Catalyst in organic reactions (Ullmann, Sonogashira coupling, C-C bond formation).​

Cloud seeding for rainfall enhancement; semiconductor (p-type).​

Synthesis of Cu(I) complexes and in feed additives.​

Handling and Safety

Weak redox properties; stable but discolors on oxidation to I₂. Harmful if swallowed/inhaled, irritant; store sealed, away from oxidizers.​

For catalog purposes: “Copper Iodide (CuI) ≥99%, white/light gray powder, mp 606 °C, poorly water-soluble, catalyst for organic synthesis; light-sensitive.”​