Cesium bromide

Bromine can function as a solvent. One of the very few metal bromides that has significant solubiUty in bromine is cesium bromide, 19.3 g/100 g of solution, thus providing a method of separating cesium bromide from the other alkah bromides (12). Aluminum bromide also is reported to have significant solubiUty in bromine but the pubUshed solubiUty values are not in good agreement (13). Bromine serves as the solvent in some brominations of organic compounds, such as 1,2-diphenylethane (14). 

Cesium Halides. Cesium bromide, [7787-69-1], CsBr, mol wt 212.82, theoretical cesium content 62.45%, is a colorless crystalline soUd, having a melting point of 636°C, a specific gravity of 4433 kg/m, and a solubUity of 1.23 kg/L of water at 25°C. It is usuaUy prepared by neutrali2ing the carbonate or hydroxide with HBr, but it is also the primary product of the Dow process (25) for poUucite processing. 

Cesium bromide [7787-69-1 ] M 212.8, m 636°, b cn 1300 , d 4.44. Very soluble in H2O, soluble in EtOH but insoluble in Me2CO. Dissolve in the minimum volume of H2O, filter and ppte by adding Me2CO. Filter solid and dry at 100°. Also recrystd from water (0.8mL/g) by partial evaporation in a desiccator. 

Due to the above requirements, typical optically-transparent materials, such as oxides (glass, quartz, alumina, zirconium oxide etc.) and halides (sodium chloride, lithium fluoride, calcium fluoride, potassium bromide, cesium bromide etc.) are usually unsuitable for use with fluoride melts. Therefore, no standard procedure exists at present for the spectral investigation of fluoride melts, and an original apparatus must be created especially for each particular case. 

Estimate the density of each of the following solids from the atomic radii of the ions given in Fig. 1.48 (a) calcium oxide (rock-salt structure, Fig. 5.39) (b) cesium bromide (cesium chloride structure, Fig. 5.41). 

CsBr CESIUM BROMIDE 1537.6463 -1.0591E+05 -5.2949E+02 1.7992E-01 -2.3362E... 

Cesium bromide (CsBr) crystals are used in scintillation counters to detect radiation. The compound is also used to coat the inside of fluorescent screens. 

Bromine combines with rubidium and cesium bromides forming solid poly-bromo complexes that can be crystallized from aqueous solutions. The complexes are soluble in liquid bromine. 

Used to introduce chromophores into amines in acetone as a solvent, with cesium bromide as a catalyst it is suggested that elevated temperatures (up to 80°C) are necessary for the complete derivatization of compounds containing diisopropylamines Reference 29... 

The structure of sodium chloride, which is the prototype for most of the alkali halides, is best described as a cubic closest packed array of Cl- ions with the Na+ ions in all of the octahedral holes [see Fig. 16.42(b)]. The relative sizes of these ions are such that rua 0.66i ci-> so this solid obeys the guidelines given previously. Note that the CP ions are forced apart by the Na+ ions, which are too large for the octahedral holes in the closest packed array of CP ions. Since the number of octahedral holes is the same as the number of packed spheres, all the octahedral holes must be filled with Na+ ions to achieve the required 1 1 stoichiometry. Most other alkali halides also have the sodium chloride structure. In fact, all the halides of lithium, sodium, potassium, and rubidium have this structure. Cesium fluoride has the sodium chloride structure but because of the large size of Cs+ ions, in this case the Cs ions form a cubic closest packed arrangement with the F ions in all the octahedral holes. On the other hand, cesium chloride, in which the Cs+ and CP ions are almost the same size, has a simple cubic structure of CP ions, with each Cs+ ion in the cubic hole in the center of each cube. The compounds cesium bromide and cesium iodide also have this latter structure. 

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