Lanthanum bromide

Lanthanum(III) bromide

Names
IUPAC names Lanthanum(III) bromide Lanthanum tribromide
Identifiers
CAS Number	13536-79-3 Y
3D model (Jmol)	Interactive image
ChemSpider	75393 Y
ECHA InfoCard	100.033.527
EC Number	36-896-7
PubChem CID	83563
InChI InChI=1S/3BrH.La/h3*1H;/q;;;+3/p-3 Y Key: XKUYOJZZLGFZTC-UHFFFAOYSA-K Y InChI=1/3BrH.La/h3*1H;/q;;;+3/p-3 Key: XKUYOJZZLGFZTC-DFZHHIFOAJ
SMILES Br[La](Br)Br
Properties
Chemical formula	LaBr3
Molar mass	378.62 g/mol (anhydrous)
Appearance	white solid, hygroscopic
Density	5.06 g/cm3, solid
Melting point	783 °C (1,441 °F; 1,056 K)
Boiling point	1,577 °C (2,871 °F; 1,850 K)
Solubility in water	Not Published Yet (very soluble in water)
Structure
Crystal structure	hexagonal (UCl3 type), hP8
Space group	P63/m, No. 176
Coordination geometry	Tricapped trigonal prismatic (nine-coordinate)
Hazards
EU classification (DSD)	not listed
Flash point	not flammable
Related compounds
Other anions	Lanthanum(III) fluoride Lanthanum(III) chloride Lanthanum(III) iodide
Other cations	Cerium(III) bromide Praseodymium(III) bromide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Lanthanum(III) bromide (LaBr₃) is an inorganic halide salt of lanthanum. When pure, it is a colorless white powder. The single crystals of LaBr₃ are hexagonal crystals with melting point of 783 °C. It is highly hygroscopic and water-soluble. There are several hydrates, La₃Br·X H₂O, of the salt also known. It is often used as a source of lanthanum in chemical synthesis, and is being evaluated for use as a scintillation material in certain applications.

Cerium activated lanthanum bromide is the recent inorganic scintillator which has a combination of high light yield and the best energy resolution.

Recent advances in scintillator material have resulted in the development of cerium activated lanthanum bromide (LaBr₃) detectors. LaBr₃ was discovered in 2001. These detectors offer improved energy resolution, fast emission and excellent temperature and linearity characteristics. Typical energy resolution at 662 keV is 3% as compared to sodium iodide detectors at 7%. The improved resolution is due to a photoelectron yield that is 160% greater than is achieved with sodium iodide. Another advantage of LaBr₃ is the nearly flat photo emission over a 70 °C temperature range (~1% change in light output).

Today LaBr₃ detectors are offered with bialkali photomultiplier tubes (PMT) that can be two inches in diameter and 10 or more inches long . However, miniature packaging can be obtained by the use of a silicon drift detector (SDD) or a Silicon Photomultiplier (SiPM). These UV enhanced diodes provide excellent wavelength matching to the 380 nm emission of LaBr₃. A paper presented at the 2005 IEEE Nuclear Science Symposium shows that the SDD has a higher quantum efficiency over the PMT. Moreover, the SDD is not as sensitive to temperature and bias drift. The reported spectroscopy performance of the SDD configuration resulted in a 2.8% energy resolution at 662 keV for the detector sizes considered.