Caesium bromide

We are now led to introduce a second empirical correction into our calculations. The theoretical values for the rubidium, caesium, bromide, and iodide ions in Table III resulted from the assumption that SE is independent of Z, which is known not to be true for these structures, on account of the difference between SE<1 and SEw. The solution values of R, which we may assume to hold also for gaseous ions in these cases, also show that the screening constant for the negative ions should be larger and for the positive ions smaller than that used that is, as Z increases SE decreases, presumably approaching our theoretical values for Z large. We shall assume that SE is a linear function of Z in this region, and evaluate the parameters of the function with the use of the solution values for the bromide and iodide ions. If we write... 

The preparation oi the alkali bromides.—While V. Merz and W. Weith 2 found that metallic sodium reacts very slowly with bromine such that even after the two elements have been kept for 8 hrs. at 200°, the conversion of sodium into the bromide is but superficial potassium, caesium, and rubidium unite with bromine more quickly, forming the alkali bromide. The bromides are also formed when hydro-bromic acid is neutralized with the alkali hydroxide or carbonate, and the soln. evaporated. This method, for example, has been used for preparing rubidium bromide, RbBr. C. Chaubrie and N. N. Beketofi made a soln. of caesium bromide, CsBr, by the double decomposition of caesium sulphate, and barium bromide. P. Klein 3 made lithium bromide by digesting calcium bromide with lithium carbonate... 

H. Topsoe found the refractive indices of crystals of potassium bromide to be 1 5546 for the C-line 1"5593 for the D-line 15715 for the F-Iine and 1-5814 for the H-line. Similar results were obtained by M. SprockhofE, and for rubidium bromide, 1 5483 for the C-line 1 5528 for the Z)-line and 1 5646 for the F-line. For the caesium bromide, M. SprockhofE obtained T6924 for the C-line 1 6984 for the D-line and 1 7126 for the F-line. The refractive index /u. of soln. of lithium, sodium, and potassium bromides have been determined by G. P. Baxter and for potassium bromide soln. by A. H. Borgesius,27 at 18° for the D-line. The fractional increase in the refractive index (/u.—p0)/w of soln. containing w per cfent. of the salt per litre, is... 

H. L. Wells and H. L. Wheeler found that when caesium bromide is shaken up with a large excess of bromine there is no separation of the tribromide as is the case when the theoretical amount of bromine is used. The colour of the soln. is lighter than bromine, and the soln. deposits dark-red crystals when evaporated spontaneously at 0°. Analyses agree with the formula caesium pentabromide, CsBr5. The crystals are rather unstable. 

Fio. 5. a. Caesium bromide, CsBr. Left, structure. Right, shape of crystal, b. Hexa-methylbenzene, CB(CH3)6. Left, structure. Right, shape of crystal, c. Copper. Left, structure. Right, shape of crystal. 

GC isotope ratio mass spectrometry [7] and GC using a caesium bromide thermionic detector [8] have been used to determine, respectively, carboxylic ethers in apples and tetraethyl pyrophosphate in chloroform-acetone extracts of crops in amounts down to 0.01 ppm. 

Phosphorus type - - Alkali metal thermionic Caesium bromide vapour detection - [403]... 

T. Gilson, M. Webster, and G. P. McQuillan The Stereochemistry of Addition Compounds of Silicon Tetrahalides, Studied by Their Spectra in the Caesium Bromide Region. J. chem. Soc. 1964, 238—44. 

Caesium Brom-palladite, Cs2PdBr4, is precipitated as a dark brown mass on mixing concentrated solutions of caesium bromide and palladous bromide.2 Upon recrystallisation from dilute hydrogen bromide solution, fine reddish brown needles are obtained, which are anhydrous, and very soluble in wrater. 

Caesium bromide, CsBr.—The bromide is produced by the interaction of caesium sulphate and barium bromide.7 It forms anhydrous8 cubic crystals, melting at 627° C., and boiling at 1800° C.9 The vapour-pressure in atmospheres is given by the expression10... 

An infrared spectrum of the tetrafluoride in a Nujol mull, with sodium chloride and caesium bromide plates, had peaks at 675 cm." (sharp) and at 576 cm." (broad). A magnetic susceptibility measurement, at 23° by the Gouy technique, showed it to be diamagnetic. 

HBrpoiid+NaOHsoiid=N aBrpoiid+H20aoiid+34 Cals., and for potassium hydroxide, 41 7 Cals. Potassium bromide is nearly twice as soluble as the corresponding chloride in water at 0°. A. von Weinberg obtained 150 1 Cals, for the heat of dissociation of lithium bromide 140 1 Cals, for sodium bromide 144 2 Cals, for potassium bromide 145 0 Cals, for rubidium bromide and 145 8 for caesium bromide. 

Caesium bromide has CsCl structure (body centered cubic type of lattice). Its density is 4.49 gm cc-1. The side of the unit cell calculated ... 

SiBr and Sil fundamentals may fall beyond the range of the potassium bromide prism, but can usually be detected with caesium bromide optics222,234,235,240. The tendency of the halosilanes to react with traces of moisture to form siloxanes must not be overlooked when working with these materials241. 

Caesium bromide Cesium bromide Cesium bromide (CsBr) EINECS 232-130-0 NSC 84269 Tricesium tribromide. Crystals for infrared spectroscopy, scintillation counters, fluorescent screens. Crystals mp = 636" bp = 1300" d = 4.44 very soluble in H2O, soluble in EtOH, insoluble in Me2CO LDso (rat ip) =1.4 g/kg. Cabot Carbon Ltd. Cerac Noah Chem. 3973Atomergic Cabot Cerac Chemetals Chemical Noah. 

Te Caesium Bromide Te Potassium Bromide Te Rubidium Bromide Te Caesium Chloride Te Rubidium Chloride... 

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