Cerium(III) bromide is an
inorganic compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...
with the formula CeBr
3. This white
hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment, which is usually at normal or room temperature. If water molecules become suspended among the substance ...
solid is of interest as a component of
scintillation counter
A scintillation counter is an instrument for detecting and measuring ionizing radiation by using the excitation effect of incident radiation on a scintillating material, and detecting the resultant light pulses.
It consists of a scintillator w ...
s.
Preparation and basic properties
The compound has been known since at least 1899, when Muthman and Stützel reported its preparation from cerium sulfide and gaseous
HBr. Aqueous solutions of CeBr
3 can be prepared from the reaction of Ce
2(CO
3)
3·H
2O with HBr. The product, CeBr
3·H
2O can be dehydrated by heating with NH
4Br followed by sublimation of residual NH
4Br. CeBr
3 can be distilled at reduced pressure (~ 0.1 Pa) in a quartz ampoule at 875-880 °C.
Like the related salt
CeCl3, the bromide absorbs water on exposure to moist air. The compound melts congruently at 722 °C, and well ordered single crystals may be produced using standard crystal growth methods like
Bridgman Bridgman is a surname, and may refer to:
* David Bridgman, Australian architect
* Elijah Coleman Bridgman (1801–1861), American missionary in China
* Frederick Arthur Bridgman (1847-1928), American artist
* George Bridgman (1865-1943), anatomist ...
or
Czochralski.
CeBr
3 adopts the hexagonal, UCl
3-type crystal structure with the P6
3/m
space group.
The cerium ions are 9-coordinate and adopt a
tricapped trigonal prismatic geometry.
The cerium–bromine bond lengths are 3.11 Å and 3.16 Å.
Applications
CeBr
3-doped lanthanum bromide single crystals are known to exhibit superior scintillation properties for applications in the security, medical imaging, and geophysics detectors.
Undoped single crystals of CeBr
3 have shown promise as a γ-ray
scintillation detector in nuclear non-proliferation testing, medical imaging,
environmental remediation
Environmental remediation deals with the removal of pollution or contaminants from environmental media such as soil, groundwater, sediment, or surface water. Remedial action is generally subject to an array of regulatory requirements, and may al ...
, and oil exploration.
Suppliers
Sigma-Aldrich
References
{{Lanthanide halides
Cerium(III) compounds
Bromides
Lanthanide halides