AVS 52nd International Symposium
    Nanometer-Scale Science and Technology Monday Sessions
       Session NS1-MoM

Paper NS1-MoM7
The Electronic Structure of Diamondoids Measured with Synchrotron Radiation

Monday, October 31, 2005, 10:20 am, Room 204

Session: Nanometer Scale Structures
Presenter: T.M. Willey, Lawrence Livermore National Laboratory
Authors: T.M. Willey, Lawrence Livermore National Laboratory
C. Bostedt, Technische Universität Berlin, Germany
T. van Buuren, Lawrence Livermore National Laboratory
J.E. Dahl, MolecularDiamond Technologies, Chevron Texaco
S.G. Liu, MolecularDiamond Technologies, Chevron Texaco
R.M.K. Carlson, MolecularDiamond Technologies, Chevron Texaco
T. Möller, Technische Universität Berlin, Germany
L.J. Terminello, Lawrence Livermore National Laboratory
Correspondent: Click to Email
Although the Group IV semiconductors Si and Ge show quantum confinement effects in nanoparticles, diamond particles a few nanometers in size do not show this increase in band-gap. However, various calculations on diamond predict increasing HOMO-LUMO gap as the diameter decreases below 1 nm. We have tested this hypothesis and will present the first measurements of the electronic structure of diamond in this near- and sub- nanometer size regime using synchrotron radiation techniques. Pure, defect-free, hydrogen-terminated diamondoids were investigated in the gas phase to eliminate particle-particle interaction and ensure measurement of pristine molecules. X-ray absorption probes the unoccupied electronic states; the carbon K-edge reveals rich electronic structure in these materials. We will present our analysis showing the emergence of a diamond-like band structure and a comparison to the predicted change in HOMO-LUMO gap from several calculations and our own recent X-ray absorption and emission measurements on solid-state diamondoids.