A carbon allotrope based on "sp" hybridization containing alternating triple and single bonds (an acetylenic or linear carbon allotrope) has been prepared. Studies of small (8 to 28 carbon atoms) acetylenic carbon model compounds show that such species are quite stable (130 degrees to 140 degrees C) provided that nonreactive terminal groups or end caps (such as tert-butyl or trifluoromethyl) are present to stabilize these molecules against further reactions. In the presence of end capping groups, laser-based synthetic techniques similar to those normally used to generate fullerenes, produce thermally stable acetylenic carbon species capped with trifluoromethyl or nitrile groups with chain lengths in excess of 300 carbon atoms. Under these conditions, only a negligible quantity of fullerenes is produced. Acetylenic carbon compounds are not particularly moisture or oxygen sensitive but are moderately light sensitive.

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New methods for synthesising poly(carbon monofluoride) (CF,),, and tetracarbon monofluoride C, F are reported. Pyrolytic graphite has been fluorinated and a new compound, graphite oxyfluoride, has been prepared. Poly-(carbon monofluoride) has been prepared in a flow reactor, in a fluidized-bed reactor, and in a high-pressure bomb reactor and tetracarbon monofluoride has been prepared by a high-pressure bomb technique. Some new structural data are presented for poly(carbon monofluoride). Recently, poly(carbon monofluoride) has been found to have a high potential as a solid lubricant and as a cathode material in high-energy batteries. POLY(CARBOK MOKOFLUORIDE) (CFX)?& has been knownsince 1934, when Ruff et al.l prepared a grey compound of composition CFo.92. reported a series of compositions, cF0.68 to cFo.995, varying from black in the case of CFo.6s through grey to white in the case of CFo.995. Tetracarbon monofluoride (C,F) was reported by W. and G. Riidoff in 1947. Reviews of the chemistry of these compounds have been published by Rudorff and H e n ~~i g . ~Very recently a series of Japanese publications on carbon monofluoride have a ~p e a r e d . ~ The poor reproducibility of these syntheses for carbon monofluoride, although not generally appreciated by fluorine chemists due perhaps to the widespread review of the synthesis, has been noted by several a ~t h o r s . l > ~, ~ Indeed it is nearly impossible to obtain significant quantities of white or even light grey carbon monofluoride by employing previous preparations, a grey material of stoicheiometry CFo.68 to CF,., normally being obtained.Samples of carbon monofluoride from our laboratories have been tested by the Lewis Research Center of the National Aeronautics and Space Administration and by the Frakford Arsenal of the U.S. Army and found to be a superior solid lubricant especially under high In 1947 W.

A stationary nozzle accessory designed for the Siemens/Nicolet LTII low-temperature device with standard q~-coaxial nozzle arrangement is described. The attachment is easy to assemble and its compatibility allows interchanging between both systems in less than l h, if required. Implementation of the stationary nozzle reduces the consumption of liquid nitrogen by more than 40% and extends the temperature range available for data collection by 60 K in the lower temperature range. Details of construction are presented, and a comparison with the tpcoaxial nozzle is discussed.

Liquid and supercritical carbon dioxide swell potassium carboxylate perfluoropolyether (PFPE-K) cylindrical micelles in water to produce novel CO(2)-in-water (C/W) microemulsions. The swelling elongates the micelles significantly from 20 to 80 nm as the molar ratio of CO(2) in the micelles to surfactant (R(CO2)) reaches approximately 8. As the micelles swell to form microemulsions, the solubility of pyrene increases by a factor of ca. 10. Fluorescence spectra suggest that pyrene resides primarily in the low-polarity micelle core rather than in the palisade region. The results illustrate the ability of C/W microemulsions to solubilize both lipophilic and fluorophilic substances simultaneously.