Chemistry 362 Spring 2018 Dr. Jean M. Standard January 24, 2018

The deBroglie Wavelength of Buckminsterfullerene and Other Large Molecules Recent measurements of the diffraction of molecules of C60, buckminsterfullerene, suggest that fullerenes are so far the largest objects in which wave-like behavior has been detected to date (see attached summary from PhysicsWeb.org). The structure of the buckminsterfullerene molecule is shown below.

The diameter of the buckminsterfullerene molecule is approximately 7 Å, or 0.7 nm. The deBroglie wavelength of the buckminsterfullerene, calculated from the diffraction pattern observed in the experiment, was 0.025 Å, or 0.0025 nm. This is probably approaching the limits of detectable deBroglie wavelengths. [In this particular experiment, the distance between slits in the double slit experiment was 100 nm.] A few other examples of deBroglie wavelength measurements are reported in the table below.

Molecule Reference # atoms Mass (amu)

Approximate size (nm)

λdeB (nm)

C60 1 60 720 0.7 0.0025 C60 2 60 720 0.7 0.0028 PFNS8a 3 356 5672 4 nm 0.0011 TPFF84b 3 202 2814 5 nm 0.0015

a PFNS8 is a perfluorinated alkyl C60 molecule. b TPFF84 is a perfluorinated alkyl derivative of a tetraphenyl porphyrin molecule.

References 1. Arndt, M.; Nairz, O.; Vos-Andreae, J.; Keller, C.; van der Zouw, G.; Zeilinger, A. Nature 1999, 401, 680-682. 2. Nairz, O.; Arndt, M.; Zeilinger, A. Am. J. Phys. 2003, 71, 319-325. 3. Gerlich, S.; Eibenberger, S.; Tomandl, M.; Nimmrichter, S.; Hornberger, K.; Fagan, P. J.; Tuxen, J.; Mayor, M.;

Arndt, M. Nature Commun. 2011, 2, 263.

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http://physicsworld.com/cws/article/news/1999/oct/15/wave-particle-duality-seen-in-carbon-60-molecules