Kikuchi band

The positive A corresponds to a tilt towards the center of Kikuchi band. Then we have... 

Following such a concentration of attention on ideal systems, particularly CO on Ni, it is refreshing to find that photoemission can produce structural information in the real world also. Photoelectron diffraction effects in emission from substrate-core levels at polar angles >20° can be described semi-quantitatively in terms of Kikuchi bands, which are observed, for example, in FEED experiments at 5 300 eV. 

As one of the early applications of the EBSD technique to the study of steel products, Randle found that the technique could be used to differentiate hematite, magnetite and wustite based on their respective pattern symmetry, Kikuchi band widths and pattern intensities, although no details of the phase recognition and analysis were provided [151]. In more recent years, Higginson and co-workers further explored the capabihty of EBSD in the analyses of iron oxide scale layers growing on low and ultra-low carbon steels, leading to a continuous stream of publications of their research results [153-162]. The technique was also used in the studies of other research groups [99,109,163-166],... 

Figure 11.11 Examples of RHEED patterns obtained during non-equilibrium MBE growth of GeSn alloys, (a) Pattern for a very smooth surface as in left side of Figure 11.10 showing points on an arc. The diagonal streaks are multiple diffraction effects known as Kikuchi bands.

Sukigara and Kikuchi interpreted these experimental data by carrying out Pariser-Parr (PP) calculations on the benzenediazonium ion. On the basis of Romming s X-ray structure of the benzenediazonium ion (1963), with fixed bond integrals for the CC and CN bonds (/ Cc and / CN), but an adjustable bond integral / NN, they were able to ascribe the 259 nm and 295 nm bands to the lAx — xAi and transi-... 

There is a multiplicity of pathways for thermal dediazoniations. An analogous situation is to be expected for photochemical dediazoniations. Based on the general experience that light-sensitive reactions often involve free radical intermediates, it was commonly assumed that all photolytic dediazoniations are free radical reactions. Horner and Stohr s results (1952), mentioned above, could lead to such a conclusion. More sophisticated methods of photochemistry also began to be applied to investigations on arenediazonium salts, e. g., the study of photolyses by irradiation at an absorption maximum of the diazonium ion using broad-band or monochromatic radiation. This technique was advocated by Sukigahara and Kikuchi (1967 a, 1967 b,... 

When the electrons impinge on the crystalline sample, they interact with individual lattice planes. When these interactions satisfy the Bragg condition, they exhibit backscattering diffraction and (due to the tilted sample) are directed toward a phosphor screen where the fluorescent pattern is detected by a CCD camera. The resulting pattern consists of a large number of intersecting bands, known as Kikuchi lines, which represent the unique crystallographic properties of the crystal... 

Parallel phosphorescence studies indicated that the O—O band for cinnamic acid occurred at 20,000 cm-1. Tsuda 43> reported a value of 17,600 cm-1. In the same study Kikuchi and Nakamura 42> measured the quenching of the phosphorescence of cinnamic acid with a group of typical sensitizers, among which were 2-nitro-fluorene and -nitroaniline. The critical separation distance between cinnamic acid and sensitizers for effective quenching was found to be 10A. 

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