Йодид гольмия (HoI3)

Description

Holmium iodide HoI3 is an anhydrous halide of the rare earth metal holmium(III). It is obtained by direct interaction of the metal with iodine (2 Ho + 3 I2 → 2 HoI3) or by the reaction of holmium with mercury(II) iodide, followed by distillation of the resulting mercury. Catalog section - inorganic salts.

Basic Attributes

• CAS No: 13813-41-7
• Chemical formula: HoI3
• Molecular Weight: 545.64
• Exact weight: 545.644
• EU number: 237-470-3
• UNII: F83S1HBF6W

Physico-chemical characteristics

• Appearance: Flakes
• Density: 5,400 g/cm³
• Melting point: 1010 °C
• Boiling point: 1300 °C (CRC handbook, 10th ed.)
• Solubility in water: soluble
• PSA specifications: 0 Ų
• XLogP3: 2.6571

Scope of application

The main consumer is lighting equipment. Holmium iodide is included in the filling of metal halide lamps: in an arc discharge, the salt evaporates and dissociates, creating a high concentration of holmium atoms in the arc zone, which significantly increases the radiation efficiency. Holmium iodides are used in high-power lighting devices for filming and in HMI-type lamps, where a mixture of dysprosium, holmium and thallium iodides is used - such sources are installed on film sets, in solar radiation simulators and in event lighting. Limitation: HoI3 disrupts the tungsten-halogen cycle in ceramic metal halide lamps, causing these lamps to have poor lumen retention.

Other directions

• starting material for the synthesis of other holmium compounds
• raw materials for the production of metallic holmium and alloys

Storage and handling

Anhydrous iodides of rare earth metals are hygroscopic and hydrolyze in air, so the container is kept hermetically sealed and work is carried out in a dry atmosphere or glove box.

Safety Information

• Tags: T (toxic)
• Hazard class code: 61-36/37/38
• Safety instructions: 53-22-26-36/37/39-45
• WGK Germany: 3