Photolytic Decomposition of Hydrogenated C70: C70H38 and C70D38

Manchado, A.; Iglesias-Groth, S.; Cataldo, F.
Referencia bibliográfica

FULLERENES NANOTUBES AND CARBON NANOSTRUCTURES, Volume 17, 428, pp.12

Fecha de publicación:
3
2009
Número de autores
3
Número de autores del IAC
2
Número de citas
0
Número de citas referidas
0
Descripción
The hydrogenated C70 fullerenes C70H38 and C70D38 have been photolyzed at 245nm under Ar or He flow. The photolysis rate constant have been measured: k = 1.54x10-3s-1 for C70H38, and the photolysis of C70D38 occurs at a rate of 1.17x10-3s-1. A remarkable isotope effect in the photolysis of the two molecules has been determined kH/kD = 1.32. The photolysis mechanism and products of C70H38 and C70D38 have been discussed and, based on the isotope effect, the rate determining step involves, as for other fulleranes, the activation of the C-H and C-D bond. The UV photons cause the dehydrogenation of C70H38 and C70D38 and their oligomerization. In an astrochemical context the photolysis reaction of C70H38 should produce back C70 with release of molecular hydrogen. The role of fulleranes and hydrogenated carbon with fullerene-like structure in space has been briefly discussed. C70H38 thermally treated at 600 degrees C under N2 releases H2 forming back C70, which was easily recognized from its characteristic FT-IR spectrum. The reaction is not fully reversible, and carbonaceous matter is formed as secondary product. The molar extinction coefficient of C70H38 and C70D38 has been determined in n-hexane at 214nm, the maximum of absorption of these two molecules; epsilon 214 = 6300Lcm-1mol-1 for the former and epsilon 214 = 5800Lcm-1mol-1 for the deuterated fullerane.
Proyectos relacionados
Project Image
Nucleosíntesis y procesos moleculares en los últimos estados de la evolución estelar
Las estrellas de masa baja e intermedia (M < 8 masas solares, Ms) representan la mayoría de estrellas en el Cosmos y terminan sus vidas en la Rama Asintótica de las Gigantes (AGB) - justo antes de formar Nebulosas Planetarias (NPs) - cuando experimentan procesos nucleosintéticos y moleculares complejos. Las estrellas AGB son importantes
Domingo Aníbal
García Hernández