ytterbium(III) Chloride
Properties
| State | Solid (hygroscopic; commonly hydrated) |
| Color | white to pale yellow |
| Solubility | Very soluble in water; soluble in alcohols |
| Melting Point | 896 °C (anhydrous) |
About ytterbium(III) Chloride
Ytterbium(III) chloride is a white-to-pale-yellow hygroscopic salt — anhydrous YbCl3 has a molar mass of 279.4 g/mol, but you almost never buy it that way. The bottle on the shelf is the heptahydrate or hexahydrate, because the anhydrous form is a pain to make from solution: dehydrating the hydrate in moist air gives YbOCl (the oxychloride) instead of clean YbCl3. To get genuinely anhydrous material you either vacuum-sublime it, heat the hydrate with NH4Cl under argon, or react Yb metal with Cl2 directly. In the solid state the Yb(III) center sits in a 9-coordinate tricapped trigonal prism, the typical geometry for the larger trivalent rare-earth cations. YbCl3 is the workhorse precursor for ytterbium chemistry: doped crystals, fiber-laser preforms, Yb(II) reduction studies (YbCl2 is reachable via sodium-naphthalenide reduction in THF), and — most usefully for the synthesis community — it is the starting material for ytterbium(III) triflate, the most popular water-tolerant Lewis acid catalyst in modern green chemistry.
Where you'll encounter it
If you've ever ordered a rare-earth chloride from Strem or Sigma-Aldrich for an organometallic project, you've likely opened a brown glass bottle of YbCl3·6H2O sitting in a desiccator, and watched it start to bead with water the moment the lid came off. In a synthesis lab, the most common job for YbCl3 is feeding the next bench over: you weigh out the hydrate, dissolve it in degassed water with triflic acid, and recover Yb(OTf)3 after evaporation and drying. In a laser-materials facility, YbCl3 is the dopant source that goes into the precursor melt for Yb:YAG single-crystal growth or into the modified-chemical-vapor-deposition (MCVD) process for Yb-doped silica fiber preforms — the same fibers that end up in 10-kilowatt cutting lasers on factory floors.
Common Uses
- Precursor for synthesis of ytterbium(III) triflate Lewis-acid catalyst
- Dopant feedstock for Yb:YAG single-crystal growth and Yb:silica fiber preforms
- Starting material for organolanthanide complexes via salt metathesis
- Source of Yb(II) reagents after reduction with sodium-naphthalenide in THF
- Lanthanide reference standard in ICP-MS calibration of rare-earth analyses
Safety Information
GHS classification: Skin irritation Category 2 (H315), Eye irritation Category 2A (H319), STOT SE Category 3 respiratory tract irritation (H335). Acute oral toxicity is moderate (LD50 oral rat for related YbCl3·6H2O around 480 mg/kg). The hydrate releases small amounts of HCl on heating or contact with strong dehydrating reagents, so handle in a fume hood when sublimating or reacting with NH4Cl. There is no OSHA PEL specific to ytterbium compounds, but follow the general inert-dust limit of 15 mg/m3 total / 5 mg/m3 respirable. Standard PPE: nitrile gloves, splash goggles, lab coat. Store sealed under desiccant.
This safety summary is for educational reference only and may not be complete. It is not a substitute for Safety Data Sheets (SDS), medical advice, or professional chemical safety guidance. Always consult appropriate SDS and qualified professionals before handling chemicals.