Anti-phase

In Figure 1(b) we have plotted the negative of anti-phase boundary energy e = — ( as a function of band filling for Pd Vi- with x = 0.25, 0.5 and 0.75. The number of zeros is in agreement with the arguments based on moments (there has to be at least four zeros). ... 

Figure 3 High resolution electron micrograph for Cu-Au LXq ordered phase [29]. Black and white dots indicate different species and black stripes are Anti Phase Domain boundaries. The lattice mismatch across the domain boundary is clearly observed by referring to the guide lines in white.

Anti-phase boundaries are interfaces leading a phase shift in the scattering amplitudes between two domains. They may be distinguished from those where the two domains differ in orientation. 

During the delay A, the proton coherence associated with long-range heteronuclear couplings is fully converted into anti-phase (AP) magnetization. The second 90° pulse applied on the 13C channel converts this AP magnetization into heteronuclear multiple quantum coherences (2HxCy). 

Differential relaxation of in-phase and anti-phase operators involving a spin C [10], which are due to additional Tj relaxation effects active only for the anti-phase components and which depend on the geometry of the spin system, can lead to systematic errors of the coupling constant derived from cross-peak multiplets observed in an E. COSY-type experiment [11]. Since these errors depend for a given differential relaxation rate Ap on the frequency difference of the coherences with C in the a or yS state, according to Eq. (1) a remedy to the problem is to maximize the relevant J such that the condition J 3> Ap/2n is fulfilled ... 

In the preparation period of the out-and-back correlation experiment, in-phase coherence Bx evolves into anti-phase coherence 2ByCz during r, a subsequent 90°X(B,C) pulse converts these two operators to Bx and 2BzCy, which evolve and give rise to a reference... 

Fig. 8.4 Schematic representation of the pulse program IPAP-[ l-l-15N]-HSQC. Narrow and wide bars represent 90° and 180° pulses, with phase x unless indicated. The white bars represent pulses that are applied only when the anti-phase spectrum is acquired. The anti-phase and in-phase...

Fig. 8.6 Schematic representation of the modified experiments HNCO (a) and (HA)CA(CO)NH (b) to measure residual dipolar couplings. The white bars represent the extra pulses that are applied in an interleaved manner to collect the in-phase 15N magnetization. The anti-phase 15N...

Figure 3.41. The oI40-AuCu(II) structure. This superstructure contains 10, slightly distorted, tP4-AuCu( I) pseudo-cells. The long-period ordering corresponds to a periodic shift of the structure (every five cells along the orthorhombic Yaxis) by />. (at I c) in the % c plane. The anti-phase domain contains 5 AuCu(I) pseudo-cells.

Ernst published a method for the identification of cross-peaks in two-dimensional spectra based on the recognition of their unique anti-phase portion in phase-resolved two-dimensional spectra. Glaser and Kalbitzer presented a generalized and fully automated method for the recognition of cross-peaks in two-dimensional NMR spectra. 

Nuzillard et al. developed a related method named log-abs which utilized the same extraction and centring teehnique as Keeler, but output a Z-spectrum , i.e., a plot of probability as a funetion of /. As with Keeler s method, this method was subjeet to inereasing unreliability with increased convolution and lower signal to noise. Unlike Keeler s method, it was not suited to anti-phase multiplets in two-dimensional speetra. 

Kessler et al. developed the Difference and Sums of Traces within Cosy Spectra (DISCO) technique for the extraction of couplings from the crosspeaks of two-dimensional (COSY) spectra. This post-processing technique combined selected cross-sections of these peaks in order to extract the active coupling , i.e., /ab from the cross-peak of A and B. After such combination, the active coupling was the separation of the in-phase and anti-phase DISCO peaks. DISCO requires accurate scaling of the constituent spectra and resolved cross-peaks. An alternative and simpler method for the accurate measurement of vicinal couplings from COSY spectra has been presented by Kim and Prestergard. ... 

Curcumin (108) Polyphenol Curcumin (108) Inflammation Various anti- Phase I/II Being conducted by 690-692... 

BWG and anti-phase boundary energies. The bond-breaking method first described by Flinn (I960) allows an estimate to be made for the structural component of anti-phase boundary (APB) energies. As good agreement can be obtained... 

Fig. 2.11 Structure in the vicinity of the shear plane for the shear operation (/ifcZ) [011] of a TiOj-type structure, (a) (121)5[0il] (b) (132) [0il] (c) (011)2[0il] the structure obtained after only operation (3) on TiO2 without the elimination of an oxygen-only plane. The structure is called an APB (anti phase boundary) or twin structure, and is similar to the shear structure of (110)j[li0] of ReOj (see Fig. 2.6(a)). Note the atomic arrangement in the zones framed by dotted lines (see also Fig. 2.113).

Occasionally, COSY-type artifacts appear in NOESY and ROESY spectra but these are easy to identify by their anti-phase multiplet structure. 

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