AVS 52nd International Symposium
    Surface Science Wednesday Sessions
       Session SS+EM-WeA

Paper SS+EM-WeA8
Resonant Soft X-Ray Emission and Inelastic X-Ray Scattering Studies of Electronic Structure in Metal Phthalocyanines

Wednesday, November 2, 2005, 4:20 pm, Room 202

Session: Organic Film Growth and Characterization
Presenter: K.E. Smith, Boston University
Authors: Y. Zhang, Boston University
S. Wang, Boston University
L. Plucinski, Boston University
J.E. Downes, Victoria University of Wellington, New Zealand
C. McGuinness, Trinity College Dublin, Ireland
P.A. Glans, Boston University
T. Learmonth, Boston University
K.E. Smith, Boston University
Correspondent: Click to Email
We report synchrotron radiation-excited resonant soft x-ray emission (SXE) spectroscopy and resonant inelastic x-ray scattering (RIXS) studies of the electronic structure of thin films of metal phthalocyanines (M-Pc).@footnote 1@ SXE measures the element-resolved partial density of states (PDOS) in materials. At a core level resonance, SXE measures the non-ionized PDOS associated with specific chemical sites. Furthermore, RIXS features can be observed which are related to low energy excitations in the system. We discuss the application of SXE and RIXS in the study of M-Pc. Our results are in excellent agreement with theory, but differ significantly from previously published experiments. The films were found to be highly susceptible to beam damage. We successfully circumvented this effect by continuous film translation during measurement. Resonant SXE spectra from undamaged Cu-Pc samples show spectral features near the Fermi level (E@sub F@) that, although predicted, have not previously been observed.@footnote 2@ We have also studied vanadium oxide phthalocyanine (VO-Pc), and in addition to measuring the element resolved PDOS, have observed dipole forbidden V 3d - V 3d* and O 2p - V 3d* charge transfer transitions across the band gap. The ability to accurately measure states near E@sub F@ is significant, as is the discovery that many SXE studies of organic semiconductors are dominated by beam damage effects. @FootnoteText@ @footnote 1@ Supported in part by the ACS PRF, by NSF DMR-0304960, and by DOE DE-FG02-98ER45680. The spectrometer system is funded by U.S. ARO DAAD19-01-1-0364 and DAAH04-95-0014. Experiments performed at the NSLS which is supported by the U.S. DOE, Divisions of Materials and Chemical Sciences.@footnote 2@ J.E. Downes, C. McGuinness, P.-A. Glans, T. Learmonth, D. Fu, P. Sheridan, and K.E. Smith, Chem. Phys. Lett. 390, 203 (2004).