Fluoroalkylsilanes (FAS) prove to be an interesting water-repellent coating for the recently discussed "superhydrophobic surfaces". The FAS investigated here form a self-assembled monolayer when brought into contact with a surface. They arrange at a high degree of orientation with their molecular axis perpendicular to the substrate surface. The film stability and the film thickness were observed using X-ray photoelectron spectroscopy. The orientation of the FAS molecules was investigated with polarizationdependent X-ray absorption near edge spectroscopy (XANES). Furthermore using density functional theory the molecular structure was calculated in order to aid in the interpretation of the polarization dependence of the XANES spectrum at F K-edge.

We have produced an endohedrally doped fullerene that shows a metal-like density of states at the Fermi level. Individual La@C 60 clusters deposited onto graphite exhibit a zero band gap as observed by scanning tunneling spectroscopy on single clusters at room temperature. Moreover, we find that an isolated La@C 60 cluster on graphite shows a reversible opening of a band gap at a transition temperature of ϳ28 K. The transition is associated with a freezing of the vibrational motion of the La atom inside the fullerene cage. The metallic behavior of La@C 60 is attributed to the presence of a dynamical dipole in the single cluster.

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We present a systematic study of the abundancies of metal-doped cluster cations M x C n ϩ (MϭCa, Sc, Y, La, Ce, Gd; xϭ1,2͒ produced in a laser vaporization source. The mass spectra of MC n ϩ and M 2 C n ϩ reveal the onset of endohedrally doped fullerenes from which the smallest possible cage sizes can be deduced. Y 2 C n and La 2 C n show a distinct transition from alternation odd-even to even-odd at nϭ69 and nϭ71, respectively, which can be explained by a substantial change in the doped fullerene structure, i.e., from networked to bi-endohedral systems. A metal induced cluster formation pathway is briefly discussed.

Photoelectron detachment spectra of M2(C6H6)− (M=Pt, Pd, Pb) have been measured in the gas phase using photon energies of a Nd:YAG laser. The vibrationally resolved ground state transition from the anion to the neutral reveals an adiabatic electron affinity of (2.01±0.05) eV and (0.88±0.05) eV for Pt2(C6H6) and Pd2(C6H6), respectively. A ground state vibrational energy of (24.2±1) meV has been resolved for Pt2(C6H6). The corresponding vibrational energy of Pt2(C6H6)− amounts to (19.0±1.0) meV. The ground state vibrational energies of Pd2(C6H6) and Pd2(C6H6)− are (20.3±1.0) meV and (18.0±2.0) meV, respectively. The small vibrational frequencies suggest a perpendicular coordination (C6v-symmetry) of the benzene-adsorbed transition metal dimers. Pb2, on the other hand, is bound parallel to the benzene plane (C2v-symmetry). A closed shell ground state electron configuration is postulated for Pb2(C6H6) in contrast to the triplet ground state of unreacted Pb2. The vertical electron affinity of Pb2(C6H6) is (1.95±0.05) eV.

We present vibrationally resolved photoelectron spectra of the gadolinium oxide anion GdO Ϫ using 3.495-eV photons. The molecules have been produced in a laser vaporization source and have been mass selected prior to the detachment process. An electron affinity of 1.19Ϯ0.1 eV is measured. The vibrational frequencies of the ground state and the first excited state are determined to be 790Ϯ40 and 887Ϯ40 cm Ϫ1 , respectively. A group of states at 2.6-eV binding energy is interpreted to correlate with the 4 f 7 ( 8 S) 6p( 2 P 1/2 ) ͉⍀ 6 p ͉ϭ1/2 configuration.

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