Holmium(III) oxide

Chembox new
Name = Holmium(III) oxide
OtherNames = Holmium oxide, Holmia
ImageFile = Holmium%28III%29_oxide.jpg
Section1 = Chembox Identifiers
CASNo = 12055-62-8
Section2 = Chembox Properties
Formula = Ho₂O₃
MolarMass = 377.86 g/mol
Solvent = other solvents
SolubleOther = Insoluble
MeltingPt = 2415 °C
BoilingPt = °C
Section7 = Chembox Hazards
ExternalMSDS = [http://www.espimetals.com/msds%27s/holmiumoxide.pdf External MSDS]

Holmium(III) oxide, is a chemical compound with the formula Ho₂O₃. It is sometimes used in making specialty glasses. Together with dysprosium(III) oxide (Dy₂O₃) holmium oxide is one of the most powerfully paramagnetic substances known. The oxide, also called holmia, [http://www.metall.com.cn/hoo.htm Catalog entry for Holmium(III) oxide from "Metall Rare Earths Ltd"] ] occurs as a component of the related erbium oxide mineral called erbia. Typically the oxides of the trivalent lanthanides coexist in nature. The separation of these components requires specialized methods.

It is often used to calibrate spectrophotometers, due to its spectral and absorption properties. [ [http://pubs.acs.org/cgi-bin/abstract.cgi/ancham/2002/74/i14/abs/ac0255680.html An International Evaluation of Holmium Oxide Solution Reference Materials for Wavelength Calibration in Molecular Absorption Spectrophotometry] ] It is also used in control rods in nuclear reactors, since it can absorb neutrons.

Treating holmium oxide with hydrogen chloride affords the corresponding holmium chloride.

Health effects

Holmium(III) oxide is, compared to many other compounds, not very dangerous, although repeated overexposure can cause granuloma and hemoglobinemia. If it contacts your skin or eyes, flush the site with water.

References