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Angle-dependent x-ray absorption near-edge structure (XANES) and scanning photoelectron microscopy measurements were performed to differentiate local electronic structures at the tips and sidewalls of highly aligned ZnO nanorods. The overall intensity of the O K-edge XANES spectra is greatly enhanced for small photon incident angles. In contrast, the overall intensity of the Zn K-edge XANES is much less sensitive to the photon incident angle. Both valence-band photoemission and O K-edge XANES spectra show substantial enhancement of O 2p derived states near the valence band maximum and conduction band minimum, respectively. The spatially resolved Zn 3d core level spectra from tip and sidewall regions show the lack of chemical shift. All the results consistently suggest that the tip surfaces of the highly aligned ZnO nanorods are terminated by O ions and the nanorods are oriented in the [0001̄] direction.

This study measures the x-ray-absorption spectra of a series of nanodiamond thin films with grain diameters ranging from 3.5 nm to 5 mm at the C K-edge using the sample drain current mode at room temperature. Resonance peaks resembling the C 1s core exciton are observed. The exciton state and conduction band edge are found to shift to higher energies with the decrease of the grain size indicative of the presence of the quantum confinement effect. [S0031-9007(99)

O K -, ZnL3, and K-edges x-ray absorption near-edge structure (XANES) spectra and scanning photoelectron microscopy (SPEM) spectra were obtained for ZnO nanorods with various diameters. The analysis of the XANES spectra revealed increased numbers of O2p and Zn4p unoccupied states with the downsizing of the nanorods, which reflects the enhancement of surface states when the diameter is decreased. Valence-band photoemission spectra show a significant narrowing of the valence band for the 45nm diameter nanorod. The Zn3d intensities in the Zn3d SPEM spectra are drastically diminished for all nanorods as compared to the ZnO reference film, which can be interpreted as a reduction in density of itinerant final states or in transition probability.

This work presents the O K-and Ti L 3,2-edge x-ray absorption near-edge structure ͑XANES͒ spectra of Pb x Sr 1−x TiO 3 ͑P x STO͒ and Ba x Sr 1−x TiO 3 ͑B x STO͒ compounds with various Pb and Ba concentrations. The result provides direct evidence that the Pb-O bonding strongly affects O 2p-Ti 3d hybridization in the TiO 6 octahedron of P x STO. In contrast, the Ba-O bonding does not substantially affect O 2p-Ti 3d hybridization in B x STO. The Ti L 3-edge XANES spectra show the splitting of the e g band for P x STO with x տ 0.5, which provides an evidence of Pb-induced tetragonal distortion in the TiO 6 octahedron. In contrast, e g band splitting is absent in B x STO.