Gas-phase production and photoelectron spectroscopy of the smallest fullerene, c20

ABSTRACT Fullerenes are graphitic cage structures incorporating exactly twelve pentagons1. The smallest possible fullerene is thus C20, which consists solely of pentagons. But the extreme

curvature and reactivity of this structure have led to doubts about its existence and stability. Although theoretical calculations have identified, besides this cage, a bowl and a monocyclic

ring isomer as low-energy members of the C20 cluster family2, only ring isomers of C20 have been observed3,4,5,6 so far. Here we show that the cage-structured fullerene C20 can be produced

from its perhydrogenated form (dodecahedrane C20H20) by replacing the hydrogen atoms with relatively weakly bound bromine atoms, followed by gas-phase debromination. For comparison we have

also produced the bowl isomer of C20 using the same procedure. We characterize the generated C20 clusters using mass-selective anion photoelectron spectroscopy; the observed electron

affinities and vibrational structures of these two C20 isomers differ significantly from each other, as well as from those of the known monocyclic isomer. We expect that these unique C20

species will serve as a benchmark test for further theoretical studies. Access through your institution Buy or subscribe This is a preview of subscription content, access via your

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* Learn about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS CHEMICAL SHIELDING OF H2O AND HF ENCAPSULATED INSIDE A C60 CAGE

Article Open access 22 September 2021 GAS PHASE SYNTHESIS OF THE C40 NANO BOWL C40H10 Article Open access 18 March 2023 SPHERICAL TRIHEDRAL METALLO-BOROSPHERENES Article Open access 02 June

2020 REFERENCES * Kroto, H. W. Smaller carbon species in the laboratory and in space. _Int. J. Mass Spectrom. Ions Process._ 138, 1– 15 (1994). Article  ADS  Google Scholar  * van Orden, A.

& Saykally, R. J. Small carbon clusters. Spectroscopy, structure, and energetics. _Chem. Rev._ 98, 2313–2357 (1998). Article  CAS  Google Scholar  * Yang, S. et al. UPS of 2–30-atom

carbon clusters: Chains and rings. _ Chem. Phys. Lett._ 144, 431–436 (1988). Article  ADS  CAS  Google Scholar  * Handschuh, H. _ et al._ Stable configurations of carbon clusters: Chains,

rings, and fullerenes. _Phys. Rev. Lett._ 74, 1095– 1098 (1995). Article  ADS  CAS  Google Scholar  * Wakabayashi, T. _ et al._ Photoelectron spectroscopy of C-_n_ produced from laser

ablated dehydroannulene derivatives having carbon ring size of n = 12, 16, 18, 20 and 24. _J. Chem. Phys._ 107 , 4783–4787 (1997). Article  ADS  CAS  Google Scholar  * Von Helden, G. _ et

al._ Do small fullerenes exist only on the computer? Experimental results on C+/-20 and C+/-24 . _Chem. Phys. Lett._ 204, 15– 22 (1993). Article  ADS  CAS  Google Scholar  * Heilbronner, E.

& Dunitz, J. D. _Reflections on Symmetry_ (VCH, Weinheim, 1993). MATH  Google Scholar  * Von Helden, G., Gotts, N. G. & Bowers, M. T. Experimental evidence for the formation of

fullerenes by collisional heating of carbon rings in the gas phase. _Nature _ 363, 60–63 ( 1993). Article  ADS  CAS  Google Scholar  * Kroto, H. W. The stability of the fullerenes C_n_, with

n = 24, 28, 32, 36, 50, 60 and 70. _Nature_ 329, 529– 531 (1987). Article  ADS  CAS  Google Scholar  * Piskoti, C., Yarger, J. & Zettl, A. C36, a new carbon solid. _Nature _ 393,

771–774 ( 1998). Article  ADS  CAS  Google Scholar  * Fowler, P. W. _ et al._ C36, a hexavalent building block for fullerene compounds and solids. _Chem. Phys. Lett._ 300, 369–378 (1999).

Article  ADS  CAS  Google Scholar  * Koshio, A., Inakuma, M., Sugai, T. & Shinohara, H. A preparative scale synthesis of C36 by high-temperature laser vaporization: Purification and

identification of C36H6 and C 36H6O. _J. Am. Chem. Soc._ 122, 398–399 (2000). Article  CAS  Google Scholar  * McEwen, A. B. & Schleyer, P. v. R. In-plane aromaticity and

trishomoaromaticity: A computational evaluation. _J. Org. Chem. _ 51, 4357–4368 ( 1986). Article  CAS  Google Scholar  * Wahl, F., Wörth, J. & Prinzbach, H. The pagodane route to

dodecahedranes: An improved approach to the C20H20 parent framework; partial and total functionalizations—does C20-fullerene exist? _Angew. Chem. Int. Edn Engl._ 32, 1722–1726 (1993).

Article  Google Scholar  * Prinzbach, H. & Weber, K. From an insecticide to Plato's Universe—the pagodane route to dodecahedranes: New pathways and new perspectives. _ Angew. Chem.

Int. Edn Engl._ 33, 2239– 2257 (1994). Article  Google Scholar  * Bertau, M. _ et al._ From pagodanes to dodecahedranes—search for a serviceable access to the parent C20H20 hydrocarbon. _

Tetrahedron_ 53, 10029–10040 (1997). Article  CAS  Google Scholar  * Cioslowsky, J., Edgington, L. & Stefanov, B. B. Steric overcrowding in perhalogenated cyclohexanes, dodecahedranes,

and [60]fulleranes. _J. Am. Chem. Soc._ 17, 10381–10384 (1995). Article  Google Scholar  * Beckhaus, H.-D. _ et al_. Experimental enthalpies of formation and strain energies for the caged

C20H20 pagodane and dodecahedrane frameworks. _J. Am. Chem. Soc._ 116, 11775–11778 (1994); 117, 8885 (1995). Article  Google Scholar  * Melder, H.-P. _ et al_. Unsaturated dodecahedranes -

synthesis of the highly pyramidalized, highly reactive C20H18 and C20H16 olefins. _Res. Chem. Intermed._ 22, 667– 702 (1996). * Scott, L. T. _ et al._ Corannulene. A three-step synthesis.

_J. Am. Chem. Soc._ 119, 10963–10968 ( 1997). Article  CAS  Google Scholar  * Galli, G., Gygi, F. & Golaz, J.-C. Vibrational and electronic properties of neutral and negatively charged

C20 clusters. _Phys. Rev. B_ 57, 1860–1867 (1998). Article  ADS  CAS  Google Scholar  * Duškesas, G. & Larsson, S. Bond lengths and reorganization energies in fullerenes and their ions.

_Theor. Chem. Acc._ 97, 110–118 ( 1997). Article  Google Scholar  * Haberland, H., Kornmeier, H., Ludewigt, C., Risch, A. & Schmidt, M. A double/triple time-of-flight mass spectrometer

for the study of photoprocesses in clusters, or how to produce cluster ions with different temperatures. _Rev. Sci. Instrum._ 62, 2621–2625 (1991). Article  ADS  CAS  Google Scholar 

Download references ACKNOWLEDGEMENTS We thank J. Leonhardt, G. Leonhardt-Lutterbeck, S. Ruf and C. Warth for technical assistance, and G. Seifert, S. Larsson and R. C. Haddon for

discussions. This work was supported by the BASF AG, the Deutsche Forschungsgemeinschaft, the Fonds der Chemischen Industrie, and the US National Science Foundation. AUTHOR INFORMATION

AUTHORS AND AFFILIATIONS * Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, Freiburg, 79104, Germany Horst Prinzbach, Andreas Weiler, Peter Landenberger, Fabian Wahl

 & Jürgen Wörth * Department of Chemistry, Boston College Merkert Chemistry Center, Chestnut Hill, 02467-3860, Massachussetts , USA Lawrence T. Scott & Marc Gelmont * Fakultät für

Physik, Albert-Ludwigs-Universität , Freiburg, 79104, Germany Daniela Olevano & Bernd v. Issendorff Authors * Horst Prinzbach View author publications You can also search for this author

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permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Prinzbach, H., Weiler, A., Landenberger, P. _et al._ Gas-phase production and photoelectron spectroscopy of the smallest fullerene, C20.

_Nature_ 407, 60–63 (2000). https://doi.org/10.1038/35024037 Download citation * Received: 04 October 1999 * Accepted: 06 June 2000 * Issue Date: 07 September 2000 * DOI:

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