Bromine hydrates

Brom-benzol, n. bromobenzene. calcium, n. calcium bromide, -cyan, n. cyanogen bromide, bromocyanogen. -dampf, tn. bromine vapor, -eisen, n. iron bromide, -fiasche, /. bromine bottle, -fluor, n. bromine fluoride, -gehalt, tn. bromine content, -gold, n. gold bromide, -goldkalium, n. potassium auri-bromide, potassium bromoaurate. bromhaltig, a. contaim ng bromine, Brom-hydrat, n. hydrobromide bromine hydrate. -hydrin, n. bromohydrin. 

The value of Ay for gas hydrates of Structure I reported in Table II could thus be derived30 with the aid of Eq. 25 with v — 3/23 from the composition Br2 8.47 H20 of the bromine hydrate following from Miss Mulders accurate study19 of the system Br2-f-H20 cf. Section III.C.(l). It should be possible to derive the value of Ay for hydrates of Structure II in the same way from the equilibrium composition of the SFe hydrate unfortunately the equilibrium composition of this hydrate is not known. The value of Ay for hydrates of Structure II reported in the table has been derived from the vapor pressure of the SF6 hydrate using some further assumptions (cf. Section III.C.(2)(b)). 

The best method for determining Afx for Structure II would be to measure the composition of the equilibrium hydrate of SF. Since the SFt molecules only fit into the larger cavities, the value of A pi immediately follows from this composition by virtue of Eq. 25", in the same way as Ap for Structure I followed from the composition of bromine hydrate. Unfortunately, the composition of SF6 hydrate has never been measured, and thus it had to be derived in an indirect manner from the vapor pressure of this hydrate. 

Hindered rotation, 33, 34 internal, 367 Homopolymer, 168, 183 Hot bands, 374 Hot lattice, 4, 11, 21 Hydrates, 7, 9, 21, 31, 41 crystallization, 44 Hydrochloric acid clathrates, 2 in hydroquinone, 7 Hydrogen, bound, 4, 175 bromine hydrate, 35 4- carbon dioxide system, 110 4 carbon monoxide system, 96, 108 chloride hydrate, 35 clathrates, 2 chloride, 30... 

Carl Lowig, 1803-1890. Professor of chemistry at Heidelberg, Zurich, and Breslau. He prepared bromine in 1825, but before his investigation was completed Balard had announced the discovery. Lowig discovered bromine hydrate, bromal hydrate, and bromoform, and was the founder of the Silesian chemical industry and of the Goldschmieden alumina works at Deutsch-Lissa. 

As mentioned before, clathrates are highly dynamic structures. Not only are hydrogen bonds forming the clathrate cages constantly disrupted and reformed, but also guest molecules can exhibit considerable mobility. The X-ray structure of bromine hydrate reported by the Ripmeester group illustrates this point [36]. 

H. W. B. Eoozeboom has measured the solubility of chlorine and bromine hydrates in water and expressed his results in terms of grams of chlorine per 100 grms. of soln. He found that 100 grms. of soln. contain 0 492 grm. of chlorine at —0 24°, at which temp, the solid phase present is a mixture of ice and chlorine hydrate, C12.8H20. Between 0° and 28 7° the solid phase is the hydrate alone, and the soln. has... 

Bromine Hydrate, Br2. 0H20, mw 340.0 red crysts, mp 6.8°(dec) is formed if satd bromine water is cooled in a freezing suit in the presence of Br2(Ref 4). The structure of this and other bromine hydrates has been the subject of many investigations. Hackh s(Ref 1) lists... 

Nevertheless the analogy with clathrate compounds (p. 179) does not go further since it is just the xenon hydrate (1 at. press, at — 3.40 G) which is very much more stable than the argon hydrate (1 at. at —42.8°) likewise the bromine hydrate is more stable than the chlorine hydrate. 

An additional relationship between the gas hydrate and the salt hydrate structures has been revealed by the discovery that bromine hydrate, Br2- 8.5H20, crystallizes in neither of the cubic gas hydrate structures but rather is nearly isostructural with the tetragonal tetra-n-butylammonium salt hydrates. Its ideal limiting composition would be Brj S.bHjO. 

Usually, however, the solution must be either seeded with some bromine hydrate or cooled for a short time to —5°C, after which the temperature is restored to 0°C. The precipitate is filtered on a glass filter funnel surrounded by a jacket containir ice water. 

PM3-PIF was implemented in DivCon, a semiempirical linear scaling code and then coupled with Tinker [69], a molecular dynamics code. With the DivCon/Tinker set of programs we calculated molecular dynamics trajectories for a system formed with 210 water molecules and one Br2 molecule for a total of 150 ps. Several interesting questions about bromine in liquid water solution might be addressed with this study. For example Is the hydration of a non polar but polarizable solute, hydrophobic or hydrophilic , To what extent the spectroscopic behavior of bromine in liquid water is the result of the closest neighbors interactions In this work we will address the latter since it pertains to the discussion about the performance of different methods to evaluate the transition energies to the excited states and we will leave a more detailed description of bromine hydration to a forthcoming report. 

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