Detalles de publicación
PP 013071
Gamma Radiolysis of C60 fullerene in water and water/ammonia mixtures: relevance of fullerene fate in ices of interstellar medium
Instituto de Astrofısica de Canarias, Via Lactea s/n,
38205 La Laguna, Spain
Departamento de Astrofısica, Universidad de La Laguna (ULL),
38206 La Laguna, Spain
National Center for Astronomy, KACST, P.O. Box 6086,
Riyadh 11442, Saudi Arabia
Istituto di Metodologie Chimiche, CNR, Via Salaria Km 29,300,
00016 Monterotondo Stazione Rome, Italy
INAF-Osservatorio Astrofisico di Catania, Via S. Sofia 78,
95123 Catania, Italy
Actinium Chemical Research srl, Via Casilina 1626/A00133. Rome, Italy
The gamma radiolysis of fullerene C60
dispersed in H2O, H2O/NH3,H2O/methanol and H2O/NH3/methanol was
studied at 250 and 500 kGy. It was found that C60
originally insoluble in the above mentioned hosting matrix became
soluble as a consequence of multiple hydroxylation and
oxidation reaction produced by the free radicals generatedby
the radiolysis of the hosting matrix. The changes undergone
by C60 were studied by infrared spectroscopy (FT-IR)and by
electronic absorption spectroscopy. The astrochemical con-
sequences of the present study are that C60
ejected in the interstellar medium for instance from protoplanetary and
planetary nebulae can condense together with water and
other ices in dense molecular clouds. Under the action of
high energy radiation C60 reacts with the free radicals gen-
erated from the matrix where it is embedded it is solubilized
and consequently its carbon content becomes available for
further abiotic processes of synthesis of molecules of astro-biological interest. The behavior of C60 appears comparable to that of common PAHs which are also hydroxylated and oxidized under similar conditions
dispersed in H2O, H2O/NH3,H2O/methanol and H2O/NH3/methanol was
studied at 250 and 500 kGy. It was found that C60
originally insoluble in the above mentioned hosting matrix became
soluble as a consequence of multiple hydroxylation and
oxidation reaction produced by the free radicals generatedby
the radiolysis of the hosting matrix. The changes undergone
by C60 were studied by infrared spectroscopy (FT-IR)and by
electronic absorption spectroscopy. The astrochemical con-
sequences of the present study are that C60
ejected in the interstellar medium for instance from protoplanetary and
planetary nebulae can condense together with water and
other ices in dense molecular clouds. Under the action of
high energy radiation C60 reacts with the free radicals gen-
erated from the matrix where it is embedded it is solubilized
and consequently its carbon content becomes available for
further abiotic processes of synthesis of molecules of astro-biological interest. The behavior of C60 appears comparable to that of common PAHs which are also hydroxylated and oxidized under similar conditions