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| Names | |||
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| IUPAC names Lanthanum(III) bromide Lanthanum tribromide | |||
| Identifiers | |||
3D model (JSmol) | |||
| ChemSpider |
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| ECHA InfoCard | 100.033.527 | ||
| EC Number |
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| Properties | |||
| 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) | ||
| Very soluble | |||
| Structure | |||
| hexagonal (UCl3 type),hP8 | |||
| P63/m, No. 176 | |||
| Tricapped trigonal prismatic (nine-coordinate) | |||
| Hazards | |||
| GHS labelling:[1] | |||
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| Warning | |||
| H315,H319,H335 | |||
| P261,P264,P271,P280,P302+P352,P304+P340,P305+P351+P338,P312,P321,P332+P313,P337+P313,P362,P403+P233,P405,P501 | |||
| Flash point | not flammable | ||
| Related compounds | |||
Otheranions | Lanthanum(III) fluoride Lanthanum(III) chloride Lanthanum(III) iodide | ||
Othercations | Cerium(III) bromide Praseodymium(III) bromide | ||
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |||
Lanthanum(III) bromide (LaBr3) is aninorganic halide salt oflanthanum. When pure, it is a colorless white powder. The single crystals of LaBr3 are hexagonal crystals with melting point of 783 °C. It is highlyhygroscopic and water-soluble. There are severalhydrates, La3Br·x H2O, of the salt also known. It is often used as a source of lanthanum in chemical synthesis and as a scintillation material in certain applications.
Thescintillator materialceriumactivatedlanthanum bromide (LaBr3:Ce) was first produced in 2001.[2] LaBr3:Ce-based radiation detectors offer improved energy resolution, fast emission and excellent temperature and linearity characteristics. Typical energy resolution at 662 keV is 3% as compared tosodium iodide detectors at 7%.[3] The improved resolution is due to a photoelectron yield that is 160% greater than is achieved with sodium iodide. Another advantage of LaBr3:Ce is the nearly flat photo emission over a 70 °C temperature range (~1% change in light output).[citation needed]
Today LaBr3 detectors are offered with bialkaliphotomultiplier tubes (PMT) that can be two inches in diameter and 10 or more inches long.[citation needed] However, miniature packaging can be obtained by the use of asilicon drift detector (SDD) or aSilicon Photomultiplier (SiPM).[4] These UV enhanced diodes provide excellent wavelength matching to the 380 nm emission of LaBr3. The SDD is not as sensitive to temperature and bias drift as PMT. The reported spectroscopy performance of the SDD configuration resulted in a 2.8% energy resolution at 662 keV for the detector sizes considered.
LaBr3 introduces an enhanced set of capabilities to a range ofgamma spectroscopyradioisotope detection and identification systems used in thehomeland security market. Isotope identification utilizes several techniques (known as algorithms) which rely on the detector's ability to discriminate peaks. The improvements in resolution allow more accurate peak discrimination in ranges where isotopes often have many overlapping peaks. This leads to better isotope classification. Screening of all types (pedestrians, cargo, conveyor belts, shipping containers, vehicles, etc.) often requires accurate isotopic identification to differentiate concerning materials from non-concerning materials (medical isotopes in patients, naturally occurring radioactive materials, etc.) Heavy R&D and deployment of instruments utilizing LaBr3 is expected in the upcoming years.
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