Bromine graphite

Coarse or fine crystalline graphite, in a weighing bottle, is allowed to stand over bromine in a desiccator for many hours at room temperature. The maximum weight gain of the graphite is 0.82-0.84 g. per g. of C. 

Black to blue-gray crystals, as in the starting graphite, but enlarged. Most of the Brg taken up is desorbed in air and can be washed out with water. 

Structure-. Graphite lattice with a bromine layer in every second layer vacancy. 

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Zinc—bromine storage batteries (qv) are under development as load-leveling devices in electric utilities (64). Photovoltaic batteries have been made of selenium or boron doped with bromine. Graphite fibers and certain polymers can be made electrically conductive by being doped with bromine. Bromine is used in quartz—haUde light bulbs. Bromine is used to etch aluminum, copper, and semi-conductors. Bromine and its salts are known to recover gold and other precious metals from their ores. Bromine can be used to desulfurize fine coal (see Coal conversion processes). Table 5 shows estimates of the primary uses of bromine. 

Graphite s. Bromine-graphite, Chromium trioxide- -, Potassium- -... 

Bromine vapor forms CgBr [12079-58-2] by direct addition to weU-oriented graphite. Other halogen and mixed halogen compounds have been prepared. 

Storage in inorganic solid matrix Intercalation into graphite [6,7] Carbon-bromine adduct [4] In zeolites [8]... 

In a subsequent study (S9), isotherms of bromine on pyrolytic graphite showed the presence of several phases C4 Br (n = 2 to 5). X-ray studies confirmed these to be stages 2 to 5, respectively. At intermediate concentrations, X-ray patterns showed mixtures of higher and lower stages. The density and configuration of intercalated bromine molecules were believed to be the same in all stages. Other structural types... 

The graphite-bromine-iron system has also been studied. No stoi-... 

The (compositionally) simplest mineral class comprises the native elements, that is, those elements, either metals or nonmetals that occur naturally in the native state, uncombined with others. Native gold, silver, and copper, for example, are metals that naturally occur in a ductile and malleable condition, while carbon - in the form of either graphite or diamond -and sulfur are examples of nonmetallic native elements. Next in compositional complexity are the binary minerals composed of two elements a metal or nonmetallic element combined with oxygen in the oxides, with a halogen - either fluorine, chlorine bromine, or iodine - in the halides, or sulfur, in the sulfides. The oxide minerals, for example, are solids that occur either in a somewhat hard, dense, and compact form in mineral ores and in rocks, or as relatively soft, unconsolidated sediments that melt at moderate to... 

In the case of the on graphite, polarized EXAFS was used to determine molecular orientation (26,27). The system consisted of a stack of parallel graphite sheets in which the EXAFS could be measured parallel or perpendicular to the plane of the sheets. The authors were able to show that the bromine was bound as Br and to determine the orientation of the Br molecules with respect to the plane of the graphite sheets. Polarized EXAFS proved to be a useful complement to LEED, which had been used to probe the long-range order in this system. 

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