Graphite salts

Prepared by oxidation of graphite in the presence of anhydrous acids. 

When oxidation is incomplete or the blue bisuLfate Is reduced with Fe (II), Sn (II) or with graphite itself, the product is less highly oxidized and the color is no longer blue. 

The analjrtical composition may be determined from the quantity of oxidants consumed in preparation, from the oxidizing effect 

The composition of the blue compovind corresponds (in acid) to about CJ HSO 2112804. 

The product is as crystalline as the initial graphite, but swollen and very dark blue. It may be stored only under concoitrated acid. Decomposed immediately by water, humid air, alcohol, ether, acetone and benzene. 

Probably most work has been devoted to FeCU [96-102a]. With transition elements usually only the halide of the highest oxidation state will react. One might expect that a necessary condition for intercalation would be the ability of 

In contrast to the above, Metz and Hohlwein [102a] found no indication of additionally intercalated Cl in their pure stages prepared with the addition of 1 bar chlorine gas. 

Detailed structure determinations are rather rare (FeCl3 [96, 100], Br2 [91], M0CI5 [104, 105]). In contrast to the alkali-metal compounds and the CF3COOH compounds, the relative orientation ABAB of the graphite layers is not altered by the intercalation of most of these metal chlorides, HF and bromine. For the graphite bisulfate compound apparently both types of stacking exist for the first-stage compound. 

In the FeCl3 and M0CI5 compounds (and probably in most chlorides) the basic structure of the anhydrous chlorides is preserved. The Cl-ion layers are somewhat distorted [96, 102] due to the interaction with the graphite and since some of the Cl are ionized. Moreover, a certain fraction of the M sites (corresponding to the ionized Cl) in the central M layer must be empty compared with the free M chloride. 

For intercalated layer compounds, particularly, it is easy to calculate the upper limit of composition as well as the periodicity length along the c-axis. As follows from Table 16, the apparent thickness of the reactant layers is always slightly 

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The reversible intercalation of various oxoacids under oxidizing conditions leads to lamellar graphite salts some of which have been known for over a century and are now particularly well characterized structurally. For example, the formation of the blue, first-stage compound with cone H2SO4 can be expressed by the idealized equation... 

The electrochemical intercalation into graphite leads in the most simple case to binary compounds (graphite salts) according to the schematic equations ... 

H. Krohn, F. Beck, and H. Junge, Reversible Electrochemical Graphite Salt Formation from Aqueous Salt Electrilytes, Ber. Bunsenges. Phys. Chem., 86, 704 - 710 (1982). 

THE SYNTHESIS OF THE FIRST STAGE GRAPHITE SALT Ce AsFe AND ITS RELATIONSHIP TO THE FIRST STAGE GRAPHITE/AsFs INTERCALATE... 

NOVEL GRAPHITE SALTS AND THEIR ELECTRICAL CONDUCTIVITIES ... 

Nestled Salts. A more dramatic instance of the effect of dielectric spacers in graphite salts is provided (32) by the first-stage fluoroarsenate of composition C14ASF6. This material is prepared by the routes shown in Scheme I and is identical to the first-stage component of the vacuum-stable... 

Beauchamp and Murphy [12] have concluded that the fluoride-ion affinity of SiF4 is only slightly inferior to that of BF3. Since the SiFs", although roughly 5/4 times the volume of BF4, requires no additional separation of the carbon-atom sheets [13] than does BF4, the energy expended for salts of comparable charge, Cy EF,c , should be similar. It seemed therefore that graphite salts Cy SiFs should exist [14]. 

N. Bartlett, R. N. Biagioni, G. McCarron, B. McQuillan and F. Tanzella, Salts of Aromatic Cations and Related Graphite Salts, Molecular Metals, Chap. 15, ed. W. E. Hatfield, Plenum Publishing Corp. (1979) 293. 

N. Bartlett, B. McQuillan and A. S. Robertson, The Synthesis of the First Stage Graphite Salt CgAsF and its Relationship to the First Stage Graphite/AsFs Intercalate, Mat. Res. Bull. 13 (1978) 1259-1264. 

X-ray examination are called the stages 1, 2, 3,. ... The alkali metal-graphite compounds and the graphite salts afford an opportunity for the detailed study of this type of stepwise intercalation. 

The name graphite salt is justified by the fact that in the production of these compounds graphite behaves as a true metal. The oxidizing agent takes electrons from the graphite, leaving the carbon layers positively charged and able to bind anions. 

Diotance. (A) BETWEEN Cabbon Planes IN Fikst-Stagb Graphite Salts... 

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