We have investigated monolayer and multilayer islands of La 2 @C 80 and La@C 82 molecules grown on a hydrogen-terminated Si(100)-2 × 1 surfaces by ultrahigh vacuum scanning tunneling microscopy. The observed La 2 @C 80 molecule has a spherical shape, consistent with a recent result by synchrotron X-ray measurements. The energy gap for the La 2 @C 80 multilayer islands is measured to be 1.3−1.5 eV, whereas that for La@C 82 is 0.5 eV, indicating that the I h cage of the La 2 @C 80 molecule is highly stabilized by an electron transfer from the encaged La atoms.

We have investigated monolayer and multilayer islands of La2@C80, La@C82 and La2@C72 grown on a hydrogenterminated Si(100)-2×1 surface by ultra-high-vacuum scanning tunneling microscopy/spectroscopy. The observed La2@C80 molecule has a spherical shape, consistent with a recent result by synchrotron X-ray measurements. The La2@C72 molecules are observed by STM as ellipsoids, consistent with a recent report by the 13 C-NMR structural analysis. The energy gap for the La2@C80 multilayer islands is measured to be 1.3-1.5 eV, whereas that for La@C82 is 0.5 eV, indicating that the Ih cage of the La2@C80 molecule is highly stabilized by an electron transfer from the encaged La atoms. The energy gap of the La2@C72 multi-layer islands is measured by STS as 1.0-1.2 eV, suggesting that the C72 carbon cage is stabilized by a localized electron transfer from the encaged La atoms to the fused-pentagon area of the fullerene cage.

A qLalitative stLdy of the phase shifis in coplanar waveguides (cms) with various periodically patlernea conauctive top covers is assessed experimentally. An increase in the dynamic range of tne phase Shih has been ObSeNeO by altering the CWI between needle4ke-patterned and uniform conductive top structures. A CPW with a fine-patterned top cover coated with CdS material was examined to demonstrate the potent.al applicat:on as an optically controlled CPN phase shifter.