Astrophysics of carbon

HW Kroto, DRM Walton, eds. The FuUerenes New Horizons for the Chemistry, Physics, and Astrophysics of Carbon. Cambridge, UK Cambridge University Press, 1993. 

V. S. Kuck (eds.), Fullerenes Synthesis, Properties, and Chemistry of Large Carbon Clusters, ACS Symp. Ser. 481, American Chemical Society, Washington, D.C., 1992 H. W. Kroto and D. R. M. Walton (eds.), Fullerenes New Horizons for the Chemistry, Physics, and Astrophysics of Carbon. Cambridge Univ. Press, Cambridge, 1993 H. W. Kroto (ed.), Fullerenes. Pergamon/Elsevier, London, 1993 A. Hirsch, The Chemistry of the Fullerenes. Thieme Verlag, Stuttgart, 1993 H. Aldersley-Williams, The Most Beautiful Molecule Discovery of the Buckyball. Wiley, New York, 1995. 

H. W. Kroto, The FuUerenes New Florizons for the Chemistry, Physics and Astrophysics of Carbon, Gambridge University Press, Gambridge, 1997. 

Indeed, this happens every moment in the Earth s atmosphere. The upper atmosphere is bombarded with cosmic rays fast-moving subatomic particles produced by extremely energetic astrophysical processes such as nuclear fusion in the sun. When cosmic rays hit molecules in the atmosphere, they induce nuclear reactions that spit out neutrons. Some of these neutrons react with nitrogen atoms in air, converting them into a radioactive isotope of carbon carbon-14 or radiocarbon , with eight neutrons in each nucleus. This carbon reacts with oxygen to form carbon dioxide. About one in every million million carbon atoms in atmospheric carbon dioxide is C. 

Lodders K. and Fegley B., Jr. (1997) Condensation chemistry of carbon stars. In Astrophysical Implications of the Laboratory Study of Presolar Materials (eds. T. J. Bernatowicz and E. Zinner). AIP, New York, pp. 391-423. 

The study of the effects induced by ion irradiation of solid materials, in particular solid carbons, is relevant in many fields of science and technology. Here we focus on its relevance in astrophysics. Solid carbon-bearing species are extremely abundant in space both in the gas and in the solid phases. A wide variety of solid carbons are observed in the interstellar and circumstellar medium as well as in many objects of the Solar System including those collected at or nearby Earth (interplanetary dust particles and meteorites). Observed and/or predicted carbon-bearing solids (or large molecules) include species with different hybridizations (sp, sp, sp" ) such as amorphous carbons, polycyclic aromatic hydrocarbons, fullerenes, nanodiamonds, graphite, and carbon chain molecules. The literature in the field is enormous interesting reviews can be found in a recent special volume of Speetroehimica Acta [1]. 

Are carbynes produced in laboratory carbon and C IC Ar vapors designed to simulate the properties carbon dust in astrophysical environments Field-emission scanning electron microscope (FESEM) and HRTEM studies of vapor-condensed carbon smokes showed a wide range of carbon morphologies that were free of metal impurities (at EDS detection limits), viz. 1. Ceo and higher fullerenes that agglomerated into amorphous soot grains, 2. fullerenic nanotubes and onions, 3. amorphous carbon sheets,... 

Rotundi, A. Rietmeijer, F.J.M. Colangeli, L. Mennella, V. Palumbo, P. Bussoletti, E. Identification of carbon forms in soot materials of astrophysical interest. Astron. Astrophys. 1998, 329, 1087-1096. 

A few informative properties of life come from easy category distinctions, such as the fact that all known life makes essential use of carbon and carbon-oxygen-nitrogen molecules in liquid water solution. The seemingly trivial observation that such carbaquist chemistry is ruled out if astrophysical carbon abundance lies below a certain threshold enabled Hoyle [1] to predict the 7.6 MeV carbon-12 ( C) nuclear resonance with remarkable precision because the discovery of the triple-alpha reaction synthesis of in stars happens to be a bottleneck for stellar nucleosynthesis of all the heavy elements. The pragmatic information in this prediction is easy to measure because it guided experimental characterization of nuclear structure where the existing computational capabilities could not. Similar sensitive dependence of the physical state of water has been used to define a habitable zone in planetary physics [10], which is not predictive in the same sense as carbon abundance (we already knew where the earth s orbit lies), but which creates a useful filter in the search for extraterrestrial life. 

A major aim of this technique is to identify and locate the characteristic electronic transition of carbon chain-like species. This is for two reasons (1) to be able to consider their relevance in astrophysical phenomena in view of their spectral features and (2) to plan gas-phase experiments with this knowledge. 

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