Anisotropy contributions

In the case of Co—Cr having perpendicular anisotropy there is, in principle, a competition between the uniaxial anisotropy of a hexagonal stmcture and the demagnetizing energy of the thin film. In the case of magnetically separated Co—Cr columns (particulate morphology) then also the shape anisotropy contributes to the perpendicular anisotropy. 

So far, speculations which attribute the observed upfield shifts of the NMR signals of 1 to a ring current of the cr-electrons199 (in line with the idea of cr-aromaticity8) have not been refuted. However, a less spectacular rationalization of the NMR chemical shifts in terms of local anisotropy contributions caused by the unique electron distribution of 1 (see Section IV) may also be possible200. 

The combined strategy of calculating the 19F chemical shifts has been studied for fluorobenzenes [62] in several solvents. Here crw has been found to be the dominant contribution to the total solvent-induced change of chemical shift the authors have neglected the solvent magnetic anisotropy contribution cra which is related to the short-range interactions. To obtain the agreement with the experimental data, the term [Pg.137]

Figure 16. Field dependence of the activation energy U with respect to the anisotropy contribution Uq.. Thin full lines stand for the isolated cluster thick curves stand for the interacting case.

The calculations are based on ring current and atomic diamagnetic anisotropy contributions (56) based on the intercalation overlap geometry depicted in the text. The overlap geometry corresponds to intercalation of dT-dA site. 

The overlap of proflavine with adjacent base pairs was varied until there was approximate agreement between the experimental upfield complexation shifts (Table V) and those calculated from ring current and atomic diamagnetic anisotropy contributions from the base pairs (56). The calculated upfield shifts are somewhat smaller than the experimental complexation shifts at the proflavine protons in the synthetic DNA complex (Table V). This... 

Random-anisotropy contributions, as epitomized by the a(r)-term in Eq. (34), are an important aspect of nanomagnetism, but their detailed treatment goes beyond the scope of this chapter. Some aspects of random-anisotropy magnetism will be treated in the chapter on soft magnets, and we also recommend reading or consulting the rich original and review literature [16, 48, 116, 124, 189, 193-197]. 

Abstract. This paper examines two theoretical aspects of the interference of atomic states in hydrogen which comes from the application of an external electric field F to the 2s metastable state. The radiative corrections to the Bethe-Lamb formula and anisotropy contribution to the angular distribution, which arises from interference between electric-field-induced El-radiation and forbidden Ml-radiation, are analysed. 

By taking AC susceptibility of the complex over 1-1500 Hz from 1.8 to 3K, the out-of-phase susceptibility displays frequency dependence (Figure 9.26), however, none of the curves reaches a peak at 1.8 K. The DC magnetization decay method (Figure 9.26) [113, 114] determined effective barrier to be 18.4 K and a relaxation time constant of 2 x 10 s. As discussed above, Gd + is a pure spin ion the major anisotropy contribution is the Mn + ion, which is the most well known anisotropy source in the design of SMM and SCM. 

The importance of magnetic anisotropy contributions to the chemical shift has been recognized for some time, and several quanti-... 

In general, the longitudinal relaxation rate of a hydride resonance is dominated by dipolar and chemical shift anisotropy contributions, the former being by far the most important in determining the observed relaxation time.[14] Thus a first look to the T value may provide a useful tool for structural assignments, since it immediately reports on the distances with respect to other magnetically active... 

While the molecular field tends to stabilize sublattices with symmetries [Fig. 10c, Eq. (24c)], the anisotropy contributions from the nonlinear Jahn-Teller coupling shift the sublattices towards the positions with tetragonal symmetry [Fig. 10a, Eq. (24b)]. Depending on the ratio of molecular field strength and anisotropy energy situations between the extremes (Fig. 10b) may be stabilized, as already discussed. If one approaches the phase transition, dynamic contributions become of... 

Anisotropy constants vary considerably with temperature. In most cases, anisotropy decreases steeply from a high value at low temperature and then slowly decreases down to zero at 7. The temperature dependence of the anisotropy constant for Zn,jNii Fe204 ferrites is shown in Fig. 4.27, for various compositions. At low temperatures, total anisotropy can be described in terms of anisotropy contributions from each cation (Kanamori, 1963). The anisotropy of Ni-Zn ferrites at 4 K, for example, can be obtained from contributions of Fe in octahedral and tetrahedral sites (Broese van Groenou, Schulkes Annis, 1967). The contribution from some cations, in particular Co and Fe, is positive above a given concentration of any of these cations, the anisotropy constant at low... 

Domain wall energy and thickness for a 180° wall, calculated from the minimum in exchange and anisotropy contributions (Landau Lifshitz, 1935) can be expressed respectively as ... 

Various relaxation mechanisms (DD, dipole-dipole SC, scalar SR, spin-rotation CSA, chemical shift anisotropy) contribute to Si nuclear spin relaxation, described by the time constants Ti for spin-lattice (longitudinal) and T2 for spin-spin (transversal) relaxation times (Eq. (1)). " In the absence of scalar contributions it hold for liquids that T k, T2. 

MHz ") and g p (= -410 MHz ) values. Finally, relaxation exhibits a relatively large chemical shift anisotropy contribution and valuable information about the dynamic nature of the molecules can be inferred through the analysis of F relaxation. 

Profound attention has been given to the magnetic latexes because of their special properties like superparamagnetism, high field irreversibility, high saturation field and extra anisotropy contribution. These properties are, for example, controlled by size and surface type. 

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