Structure types graphite

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... 

An example for a host molecule with a layerlike structure is graphite. Various types of both organic and inorganic inclusion compounds, as well as stoichiometric and nonstoichiometric compounds, are known. 

Furthermore, we believe that the stabilizing influence of boron in the structure of graphite is connected with enhancement of its acceptor properties, which manifest themselves when Boron atoms substitute carbon atoms in the crystalline structure (hexagon ring) of carbon. Such effects are mentioned in the literature for some types of carbon materials [3] and the influence of boron on TEG can be the similar. 

C (graph ite), hP4, structural type. In comparison with the tetrahedral structure of C diamond a very different structure is adopted by carbon in graphite. 

The AlB2-type structure can be considered a filled-up WC structure type. The B atoms form a hexagonal net and centre all the A1 trigonal prisms. The arrangement of the boron atoms in their layers is the same as that of carbon in graphite (63 layers). (See also the nThSi2, tI12, description for a comparison between the planar... 

An example is represented by the reduction of cytochrome c using a pyrolytic graphite electrode suitably prepared. In fact, as schematised in Figure 6, this type of carbon material (briefly alluded to in Chapter 3, Section 1.1) has a solid state structure fairly close to the ideal structure of graphite. 

Makovicky Hyde (1981) have reviewed incommensurate misfit structures in graphite intercalation compounds, brucite-type compounds, sulphides and related layered systems. A simple two-dimensional incommensurate system is provided by graphite with adsorbed rare gas monolayers. At low densities and high temperatures. 

Thus, we expect the puckered graphitic sheet with 90° bond angles to have the smallest normalized fourth moment and shape parameter, s, and hence to be the most stable structure for the half-full p band as is indeed observed in the middle panel of Fig. 8.5. We should also note that if the n bonding is neglected then this three-atom contribution is identically zero for = 90°, so that 5 = 0 and we have the total bimodal behaviour of the p eigenspectrum that is observed in the lower panel of Fig. 8.1 for the arsenic structure type. 

Yb-ln-Sb. The ternary YbsI Sbe compound was obtained from a direct element combination reaction in a sealed graphite tube at 973 K, and its crystal structure was determined by X-ray single crystal diffraction methods. It crystallizes in the Ba5ln2Sb6 structure type with a unit cell of a = 0.73992, b = 2.3001, c = 0.45139 (Kim et al., 2000). 

Hoffman, D. M., R. E. Heinz, G. L. Doll, and P. C. Eklund. 1985. Optical reflectance study of the electronic structure of acceptor-type graphite intercalation compounds. Phys. Rev. B 32 1278-1288. 

A number of complications lead to differences in experimental results. Aside from possible catalytic influences of impurities in the carbon, there are different structural types of carbon that have been studied. These include amorphous carbon (typically randomly oriented graphite crystals)... 

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