ХЛОРИД ДИДИМИЯ

Description

Didymium chloride is the chloride salt of the mixed rare earth metals neodymium and praseodymium, “didymium” in the historical sense of the term. Unlike didymium oxide, it is soluble in water and serves as a convenient form for introducing didymium rare earth elements into aqueous and non-aqueous technological solutions.

Basic Attributes

• CAS No: 11098-90-1
• Chemical formula: Cl6NdPr
• Molecular Weight: 497.87
• Exact weight: 364.72900
• DSSTox ID: DTXSID10648750
• PSA Features: 0
• XLogP3: 4.05490

Substance class

Refers to inorganic salts of rare earth metals - lanthanide chlorides. Like the related oxide, didymium compounds are valued for the optical properties of a mixture of neodymium and praseodymium: selective absorption of the sodium yellow line at a wavelength of about 589 nm with high transparency to the rest of the visible spectrum.

Scope of application

Didymium chloride is used as a soluble source of didymium rare earth elements in laboratory and industrial chemistry - for the preparation of other neodymium and praseodymium compounds, including oxide and organic complexes, as well as in research work requiring a water-soluble form of this mixture of lanthanides.

A common application for the group of didymium materials is the optical industry: safety glasses for glass blowers and working with hot glass and metal, light filters for flame tests and welding, photographic filters that enhance the color of autumn foliage, reference filters for calibrating spectrometers by wavelength.

Physico-chemical features

A zero value for the PSA parameter is typical for simple inorganic salts without organic functional groups. The positive value of XLogP3 (4.05) in such cards is often of a calculated, evaluative nature and is applicable with a reservation, since XLogP3 models were developed primarily for organic molecules.

The molecular and exact masses differ more significantly than is usually the case for the same substance (497.87 versus 364.72900): such a discrepancy is typical for inorganic salts of variable composition, where the molecular mass is calculated for the average gross formula, and the exact mass is calculated for the specific isotopic composition of the most common nuclides.

Storage and transportation conditions

Store in a hermetically sealed container in a dry place, since chlorides of rare earth metals are hygroscopic and can absorb moisture from the air to form crystalline hydrates. Isolate from strong bases and oxidizing agents and observe general precautions taken for inorganic metal salts.

When working with packaging and weighing, it is recommended to use gloves and safety glasses: like most soluble metal salts, didymium chloride can irritate the skin and mucous membranes upon prolonged contact, although a detailed GHS classification for this particular CAS number is not given in the dump.

Together with didymium oxide (CAS 11141-21-2), the chloride form forms an “insoluble - soluble” pair of sources of the same mixture of rare earth elements: the choice of a specific form is determined by the technological task - the oxide is convenient for direct introduction into the glass charge, chloride - for solution and electrochemical processes.