No abstract

Interaction of benzene with boron trichloride at 800°C yields a graphite-like metallic solid of composition BC3, and chlorine-pyridine mixtures at 800 "C give a nitrogen-carbon also having a graphite-like structure.

A blue-black first-stage graphite fluoride, CxF (5 > x > 2 ) , in which the planar carbon-atom sheets of graphite are preserved, is made by intercalation of graphite with fluorine in the presence of liquid hydrogen fluoride, a t ca. 20 "C, the oxidation (which is electrochemically reversible for x > 2.6) proceeding via a highly conductive second stage salt: CIZ+HF2-.The recent discovery1 in these laboratories that the intercalation of graphite by AsF,, in the presence of elemental fluorine, resulted in the incorporation of 'extra' fluorine to a limiting composition C,AsF,.+F, has prompted an examination of the factors which govern the intercalation of graphite by fluorine itself. It is common knowledge that graphite is not intercalated spontaneously by fluorine at room temperature and ordinary pressures, but that interaction between these elements does occur at higher temperatures (usually ca. 400 "C) to yield fluorides such as (CF), and (C,F),, in which the F atoms are covalently bound to tetrahedral ~a r b o n . ~~~ However, more than thirty years ago, Riidorff and Riidorff4 had discovered that graphite does intercalate fluorine spontaneously, at room temperature, in the presence of gaseous hydrogen fluoride to yield a first-stage graphite fluoride C,F with x values ranging from 3.57 to 4.03 which they termed 'tetracarbon monofluoride'. X-Ray diffraction data showed that the carbon-atom layers in their C,F materials were planar and that the F ligands were covalently bound to carbon atoms. Our work has shown that the Riidorffs' species is part of a more extensive system of true intercalation compounds including hydrofluorides, a second-stage bifluoride C12HF,, and a first-stage compound C,F (5 > x > 2). For much of this composition

Dioxygenyl hexafluoroplatinate (v) has been made from oxygen and platinum hexafluoride and by fluorinating platinum or platinum salts in the presence of oxygen. It is a red, dimorphic, paramagnetic solid which sublimes without decomposition in a vacuum above 90". X Iower-temperature, rhombohedra1 form is isomorphous with potassium hexafluoroplatinate(v) ; a higher-temperature, cubic form is isomorphous and nearly isostructural with potassium hexafluoroantimonate(v) . The pentapositive platinum complexes, KPtF,, CIF3,PtF,, and IF,,PtF5 have been derived from it.T H E fluorine chemistry of the platinum metals has recently been extended and revised.To this Weinstock and his co-workers have contributed significantly. The volatile * Presented at the Second International Symposium on Fluorine Chemistry, Estes Park, Colorado,1962.-f Dioxygenyl is preferred t o dioxygenium, to indicate the removal of one electron from dioxygen (0,) since the suffix -yl is usual for cations or radicals containing oxygen (e.g., nitrosyl and chlorosyl), whereas -ium is often used to indicate the addition of a proton.The paper by Bartlett and Quail, J., 1961, 3728, is considered Part I of this series.

New structural relatives of graphite with the composition BxCyNx have been synthesized from the interaction of boron trichloride, acetylene and ammonia at 400-700°C. A hexagonal layer structure type is indicated by X-ray and electron diffraction data. Binding energies of ls electrons (ESCA) for B, c and N indicate that each graphite-like sheet is a composite of all three elements. ~he mate~ial of approxi~at7 composition Bo.35c0.30N0.35 1s a sem1conductor and 1s 1ntercalated by both strong reducing and oxidizing agents. MATERIALS INDEX: boron-carbon-nitrogen graphites.