In-plane orientation

Go Binary and Ternary Alloyed Thin Films. Most of the thin-film media for longitudinal and perpendicular recording consist of Co—X—Y binary or ternary alloys. In most cases Co—Cr is used for perpendicular recording while for the high density longitudinal media Co—Cr—X is used X = Pt, Ta, Ni). For the latter it is essential to deposit this alloy on a Cr underlayer in order to obtain the necessary in-plane orientation. A second element combined with Co has important consequences for the Curie temperature (T ) of the alloy, at which the spontaneous magnetisation disappears. The for... 

The out-of-plane orientation of chromophores can be more easily controlled in LB films as compared with the in-plane orientation. Many chromophores are known to show anisotropic orientation in the surface normal direction. The molecular structure of chromophores and their position in amphiphile molecules, the surface pressure, the subphase conditions are among those affect their out-of-plane orientation. The out-of-plane orientation has been studied by dichroic ratio at 45° incidence, absorbance ratio at normal and 45° incidence, and incident angle dependence of p-polarized absorption [3,4,27,33-41]. The evaluation of the out-of-plane orientation in LB films is given below using amphipathic porphyrin (AMP) as an example [5,10,12]. 

Preferential in plane orientation of the charge transfer complex and rearrangement of substrate on aging were established... 

The perpendicular orientation of the alkene in such complexes is favored because it maximizes the overlap of the bond with the LUMO (dx2 — y2, Figure 13.7) and minimizes 4e repulsive interactions with the HOMO (ndz2). The in-plane orientation is not expected to be strongly disfavored, however, because of the secondary interaction between the orbital and the dxy orbital. The rotational barrier of ethylene in Zeise s anion was theoretically estimated to be 55 kj/mol [282], within the range 42-63 kj/mol measured by NMR for related complexes [286]. 

Aromatic polyimide films that are spin-coated or solution-cast with thicknesses under 15 jm exhibit structural anisotropy in the condensed state. This anisotropy is associated with the tendency of the chains to align parallel to the substrate surface, undergoing what is described as in-plane orientation. 

Fluorescence in INpOH-aliphatic amine hydrogen-bonded systems in nonpolar rigid matrices like polyethylene films at 77 K is dual in nature [200-202], The ESPT in the hydrogen-bonded complex results in two types of ion pairs, one with in-plane orientation between excited naphtholate and ammonium ions (fluorescence maximum at 395 nm with a lifetime of 5.3 nsec) and the other with an... 

Figure 27. UV spectra of anthracene and the ring fused bis-anthracene (ref. 2). On the anthracene structure are shown the in-plane orientations of the electric dipole transition moment vectors associated with the intense short wavelength UV bands (1Bb) near 250 nm and the weak long wavelength bands ( LJ near 360 nm. The Xmax for the exciton bands of bis-anthracene are red shifted from the corresponding bands in the parent, as the vectors intersect at >90°.

Figure 7.7 shows TEM and HRTEM images, partly together with the corresponding SAD patterns, of PLD ZnO films grown on Si(lll) substrates [49], Note that the lateral SAD image of the film on Si(lll) was taken from many columns as indicated in Fig. 7.7a. The ZnO columns on Si(lll) (and also on Si(100), see [49]) show no preferential azimuthal in-plane orientation relating to the Si substrate. Figure 7.7b shows a HRTEM lattice image with intermediate amorphous SiO layer of 2-4 nm thickness and an additional interdiffusion...

Figure 7.8 shows a ZnO film deposited on 3C-SiC buffered Si(lll). The CVD-grown, only 3 nm thin 3C-SiC buffer layer does not improve the in-plane orientation of ZnO on Si. As already demonstrated in Fig. 7.7, polycrystalline ZnO without any preferential in-plane orientation was found. The HRTEM inset in Fig. 7.8 shows an amorphous layer at the ZnO/3C-SiC interface, which is formed by oxidation of the CVD grown 3C-SiC film. Interestingly, these ZnO films on SiC-buffered Si are c-axis textured and show slightly improved PL and CL characteristics compared to ZnO grown directly on silicon [50]. 

FIGURE 6 Evolution of the intensity of the reflectance structures with in-plane orientation of the electric field (a) [10-10] orientation, (b) [-12-10] orientation [8], Note that the increase of Ais is accompanied by a decrease of Bu and makes it easier to detect A2S. Arrows indicate the average positions of transverse excitonic polaritons The eigenenergies, which are different for the two polarisations due to the spin exchange interaction, can be obtained from a lineshape fitting of the reflectivity spectra. 

Growth on (1120) A-plane sapphire yields an epitaxial relationship of (0001)g,n//(1 120)ai2O3 with inplane orientations of [1120]g.n//[0001]Ai2O3 and [1120]g,n//[1120]ai2O3 [2,4], This results in approximately a 30% lattice mismatch for both in-plane orientations by comparing the oxygen sublattice distance with the GaN lattice. 

Out-of-Plane and In-Plane Orientations of MS Transition Dipole Moments in J- and H-Aggregates... 

In its final state, this polyimide cannot be processed thus processing occurs before the imidization step. PAA solutions may be spin-coated onto the appropriate substrates and then thermally treated. This sequence establishes the molecular order in the material (lj 2) and in-plane orientation (3). Further development of residual stresses is also associated with this coating process. 

Figure 10 Experimental NRV S spectra of polycrystalline (powder, D (5)) and single crystal (in-plane, (v) and ont-of-plane, Dj. (v)) [Fe(TPP)(l-Mehn)(NO)]. Due to porphyrin packing in the f 2i2i2i space group, the in-plane orientation orients all porphyrin planes 13.8° from the incident beam. The out-of-plane orientation obtained by rotation of the crystal by 90° orients all porphyrin normals to within 13.8°...

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