Advertisement

Fulleranes pp 149-170 | Cite as

Isotope Effect in the UV Photolysis of Hydrogenated and Perdeuterated Fulleranes

  • Franco Cataldo
  • Susana Iglesias-Groth
  • Arturo Manchado
Chapter
Part of the Carbon Materials: Chemistry and Physics book series (CMCP, volume 2)

Abstract

Fulleranes, the hydrogenated fullerenes C60H36 and C60D36 have been synthesized in n-hexane where they show an absorption maximum at 217 nm in their electronic absorption spectra. Similarly C70H38 and C70D38 show an absorption maximum in n-hexane at 214 nm. The interstellar light extinction curve shows a “bump” just at 217 nm which is attributed to hydrogenated interstellar carbon dust. Remarkably also fulleranes which can be considered an analogous of hydrogenated carbon dust show a maximum of absorption just at 217 nm. The width of this absorption appears to be consistent with the observed widths of the UV bump. The photolysis of fulleranes with monochromatic light at 254 nm causes a shift of the absorption maximum from 217 nm to longer wavelengths. This band shift of the absorption maximum has already been observed in the photolysis or in the thermal processing of hydrogenated carbon dust. The band shift is due to the release of molecular hydrogen, a process which causes the aromatization of the carbon dust. C60H36 and C60D36 are photolyzed at a rate kC60H36 = 2.45 × 10−3 s−1 while kC60D36 = 2.27 × 10−3 s−1. This implies an isotope effect so that C60H36 is photolyzed 1.08 times faster than C60D36. In the interstellar medium this implies a deuterium enrichment of the hydrogenated interstellar carbon dust. The presence of a measurable isotope effect suggests that the photolysis of C60H36 and C60D36 involves the rupture of the C–H and C–D bond with release of H2. The hydrogenated C70 fullerenes C70H38 and C70D38 have been photolyzed at 254 nm under Ar or He flow. The photolysis rate constant have been measured: k = 1.54 × 10−3 s−1 for C70H38 while the photolysis of C70D38 occurs at a rate of 1.17 × 10−3 s−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. Fullerane C60H18 and its deuterated analogous C60D18 were synthesized in n-hexane solution by a reduction reaction of C60 under the action of HCl or DCl on Zn dust. The resulting solutions were subjected to UV irradiation at 254 nm from a low pressure mercury lamp under He. It was found that at 212 nm the photolysis rate constant of C60H18 molecule Hk212 = 8.68 × 10−4 s−1 was significantly higher than that of its deuterated analogous C60D18:Dk212 = 5.93 × 10−4 s−1. Similarly, at 256 nm it was confirmed the result that C60D18 was photolyzed more slowly than C60H18. In fact, also in this case Hk256 = 6.83 × 10−4 s−1 is significantly higher than that of its deuterated analogous C60D18:Dk212 = 3.74 × 10−4 s−1. Kinetic isotope effect involving the C–H and C–D bond activation has been advocated to explain the differences in photodecomposition speed of C60H18 in comparison to C60D18.

Keywords

Electronic Absorption Spectrum Isotope Effect Interstellar Medium Kinetic Isotope Effect Asymptotic Giant Branch 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

The present research work has been supported by grant AYA2007-64748 of the Spanish Ministerio de Ciencia e Innovacion.

References

  1. Bamford CH, Tipper CFH (1983) Modern kinetics methods. Elsevier, Amsterdam, pp 120–132Google Scholar
  2. Bensasson RV, Hill TJ, Land EJ, Leach S, McGarvey DJ, Truscott TG, Ebenhoch J, Gerst M, Ruchardt C (1997) Chem Phys 215:111–123CrossRefGoogle Scholar
  3. Cataldo F (2003a) Fullerenes Nanot Carbon Nanostruct 11:295–316CrossRefGoogle Scholar
  4. Cataldo F (2003b) Fullerenes Nanot Carbon Nanostruct 11:317–331CrossRefGoogle Scholar
  5. Cataldo F (2004) Int J Astrobiol 3:237–246CrossRefGoogle Scholar
  6. Cataldo F (2006a) Int J Astrobiol 5:37–45CrossRefGoogle Scholar
  7. Cataldo F (2006b) Origin Life Evol Biosph 36:467–475Google Scholar
  8. Cataldo F (2008) Solubility of fullerenes in fatty acids esters: a new way to deliver in vivo fullerenes. Theoretical calculations and experimental results. In: Cataldo F, Da Ros T (eds) Medicinal chemistry and pharmacological potential of fullerenes and carbon nanotubes. Springer, Berlin, pp 317–335CrossRefGoogle Scholar
  9. Cataldo F, Braun T (2007) Fullerenes Nanot Carbon Nanostruct 15:331–339CrossRefGoogle Scholar
  10. Cataldo F, Strazzulla G, Iglesias-Groth S (2008) Int J Astrobiol 7:107–116CrossRefGoogle Scholar
  11. Cataldo F, Iglesias-Groth S, Manchado A (2009a) Fullerenes Nanot Carbon Nanostruct 17:378CrossRefGoogle Scholar
  12. Cataldo F, Iglesias-Groth S, Manchado A (2009b) Fullerenes Nanot Carbon Nanostruct 17:401CrossRefGoogle Scholar
  13. Cataldo F, Strazzulla A, Iglesias-Groth S (2009c) Month Not Roy Astrophys Soc 394:615CrossRefGoogle Scholar
  14. Cataldo F, Iglesias-Groth S, Manchado A (2009d) Fullerenes Nanot Carbon Nanostruct 17:414CrossRefGoogle Scholar
  15. Colangeli L, Mennella V, Bussoletti E, Palumbo P, Rotundi A (1999) Laboratory analogues for interstellar carbon dust. In: d’Hendecourt L, Joblin C, Jones A (eds) Solid interstellar matter the ISO revolution. Springer, Heidelberg, Lecture 9Google Scholar
  16. Darwish AD, Abdul-Sada AK, Langley GJ, Kroto HW, Taylor R, Walton DRM (1995) J Chem Soc. Perkin Trans 2:2359–2365CrossRefGoogle Scholar
  17. Ehrenfreund P, Charnley SB (2000) Annu Rev Astronom Astrophys 38:427–483CrossRefGoogle Scholar
  18. Foing BH, Ehrenfreund P (1994) Nature 369:296–298CrossRefGoogle Scholar
  19. Foing BH, Ehrenfreund P (1997) Astron Astrophys Lett 317:L59–L62Google Scholar
  20. Glassgold AE (1996) Annu Rev Astronom Astrophys 34:241–277CrossRefGoogle Scholar
  21. Goeres A, Sedlmayr E (1993) Fullerene Sci Technol 1:563–570CrossRefGoogle Scholar
  22. Gourier DRF, Delpoux O, Binet L, Vezin H, Moissette A, Derenne S (2008) Geochim Cosmochim Acta 72:1914–1923CrossRefGoogle Scholar
  23. Guldi DM, Kamat P (2000). Photophysical properties of pristine fullerenes, functionalized fullerenes, and fullerene-containing donor-bridge acceptor systems. In: Kadish KM, Ruoff RS (eds)  Chapter 5 in Fullerenes: chemistry, physics and technology. Wiley-Interscience, New YorkGoogle Scholar
  24. Hare JP, Kroto HW (1992) Acc Chem Res 25:106–112CrossRefGoogle Scholar
  25. Howard JA (1993) Chem Phys Lett 203:540–544CrossRefGoogle Scholar
  26. Iglesias-Groth S (2004) Astrophys J 608:L37–L40CrossRefGoogle Scholar
  27. Iglesias-Groth S (2005) Astrophys J 632:L25–L28CrossRefGoogle Scholar
  28. Iglesias-Groth S (2006) Month Not Roy Astron Soc 368:1925–1930CrossRefGoogle Scholar
  29. Kohen A, Limbach HH (2006) Isotope effects in chemistry and biology. CRC Press/Taylor & Francis, Boca Raton, FLGoogle Scholar
  30. Kroto HW (2006) Introduction: Space-Pandora’s Box. In: Rietmeijer FJH (ed) Natural fullerenes and related structures of elemental carbon. Springer, Dordrecht, pp 1–5CrossRefGoogle Scholar
  31. Mennella V (2001) Astron Astrophys 367:355–361CrossRefGoogle Scholar
  32. Millar T (2004) Organic molecules in the interstellar medium. In: Ehrenfreund P (ed) Astrobiology: future perspectives. Kluwer, Dordrecht, pp 17–31Google Scholar
  33. Ninomiya I, Naito T (1989) Photochemical synthesis. Academic, London, p 221Google Scholar
  34. Nossal J, Saini RK, Alemany LB, Meier M, Billups WE (2001) Eur J Org Chem 2001:4167–4180CrossRefGoogle Scholar
  35. Palit DK, Mohan H, Mittal JP (1998) J Phys Chem 102:4456–4461CrossRefGoogle Scholar
  36. Petrie S, Bohme DK (2000) Astrophys J 540:869–885CrossRefGoogle Scholar
  37. Petrie S, Becker H, Baranov VI, Bohme DK (1995) Int J Mass Spectrom 145:79–88CrossRefGoogle Scholar
  38. Shaw AM (2006) Astrochemistry. Wiley, ChichesterGoogle Scholar
  39. Stoldt CR, Maboudian R, Carraro C (2001) Astrophys J 548:L225–L228CrossRefGoogle Scholar
  40. Taylor R (1999) Lecture notes on fullerene chemistry. A handbook for chemists. Imperial College Press, London, pp 56–70CrossRefGoogle Scholar
  41. Taylor R (2006) CR Chimie 9:982–1000CrossRefGoogle Scholar
  42. Tielens AGGM (2005) The physics and chemistry of the interstellar medium. Cambridge University Press, CambridgeCrossRefGoogle Scholar
  43. Unsold A, Baschek B (2002) The new cosmos: an introduction to astronomy and astrophysics, 5th edn. Springer, Berlin, p 247Google Scholar
  44. Van Dishoeck EF, Blake GA (1998) Annu Rev Astronom Astrophys 36:317–368CrossRefGoogle Scholar
  45. Wagberg T, Johnels D, Peera A, Hedenstrom M, Schulga YM, Tsybin YO, Purcell JM, Marshall AG, Noreus D, Sato T, Talyzin AV (2005) Org Lett 7:5557–5560CrossRefGoogle Scholar
  46. Webster A (1991) Nature 352:412–414CrossRefGoogle Scholar
  47. Yeremin EN (1979) The foundation of chemical kinetics. Mir, Moscow, pp 21–26Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Franco Cataldo
    • 1
    • 2
  • Susana Iglesias-Groth
    • 3
  • Arturo Manchado
    • 3
  1. 1.Istituto Nazionale di Astrofisica, Osservatorio Astrofisico di CataniaCataniaItaly
  2. 2.Actinium Chemical Research srlRomeItaly
  3. 3.Instituto de Astrofisica de CanariasLa LagunaSpain

Personalised recommendations