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Additive anisotropic

An important addition to the model was the inclusion of virtual particles representative of lone pairs on hydrogen bond acceptors [60], Their inclusion was motivated by the inability of the atom-based electrostatic model to treat interactions with water as a function of orientation. By distributing the atomic charges on to lone pairs it was possible to reproduce QM interaction energies as a function of orientation. The addition of lone pairs may be considered analogous to the use of atomic dipoles on such atoms. In the model, the polarizability is still maintained on the parent atom. In addition, anisotropic atomic polarizability, as described in Eq. (9-28), is included on hydrogen bond acceptors [65], Its inclusion allows for reproduction of QM polarization response as a function of orientation around S, O and N atoms and it facilitates reproduction of QM interaction energies with ions as a function of orientation. [Pg.243]

Additionally, anisotropic chemical shift effects will also be present in the spectrum due to the nonexistence of molecular tumbling. This means that, since in solids the atoms and molecules are not moving, they do not change the orientation. Since the ability of the applied field to generate electron currents depends on the orientation of the nuclei relative to the applied field, the chemical shift depends on orientation, and since in solids this effect is not averaged out, it will contribute to the peak broadening. The chemical shift anisotropy also varies with the angle, 9,... [Pg.176]

Fig. 8. Compositions in volume fractions of coexisting phases for rods of axial ratio x = 100 subject to interactions denoted by the parameter x. The binodal for isotropic phases is on the left that for anisotropic phases is on the right. The minimum of the shallow concave branch of the latter binodal is a critical point marking the emergence of two additional anisotropic phases. The cusp marks a triple point where three phases coexist. Calculations carried out according to the 1956 theory see Ref. Fig. 8. Compositions in volume fractions of coexisting phases for rods of axial ratio x = 100 subject to interactions denoted by the parameter x. The binodal for isotropic phases is on the left that for anisotropic phases is on the right. The minimum of the shallow concave branch of the latter binodal is a critical point marking the emergence of two additional anisotropic phases. The cusp marks a triple point where three phases coexist. Calculations carried out according to the 1956 theory see Ref.
The spinning of the individual molecules ceases upon cooling and a lattice of space group Po3 with a lattice constant of a = 10.041 A is formed. The influence of neighboring fullerene molecules has been determined for this structure due to the molecules spherical shape there are mainly van der Waals interactions, but in this case an additional anisotropic charge distribution is induced by the existence of different bond types. In the cooled crystal, a given, electron-deficient five-... [Pg.64]

In addition to the ordinary diffusion current, there is an additional anisotropic current arising from diffusional effects in systems with graded band edges such as shown in Fig. 2. Van Ruyven and Williams derived this anisotropic diffusional component of the current density ... [Pg.297]

Transverse Strength. A similar consideration holds for the transverse strength of composites. In addition, anisotropic fibers, such as Kevlar or carbon fibers, have very low transverse moduli, Ej ... [Pg.33]

The statistical thermodynamic theory makes a mean-field treatment to the crystallization energy Ep. However, in practice, thermal fluctuations for parallel ordering of local chains generally exist in the melt states of blends. Such an additional anisotropic contribution of thermal fluctuations will make the practical parallel-packing interactions larger than the mean-field estimation on the basis of the isotropic liquid, which leads to a deviation from the theoretical predictions of the phase separation binodals. [Pg.227]

In addition, anisotropic or isotropic motions can be detected which lead to a partial or full averaging of the quadrupolar coupling tensors. [Pg.293]

Hcr c decreased upon hydrogenation while H c increased with increasing x the latter was, in addition, anisotropic within the basal plane, Ha b > HaWa, for x > 0. Ha generally decreased with increasing x in the case of polycrystals, while the paramagnetic 0p dropped simultaneously from 40 to 31.5K, and ju jf remained roughly constant, 9.5 Pb... [Pg.269]

In addition anisotropic scaling allows for three possibilities for the fixed point of the nematic splay elastic constant Xi = 0, implying = vy/vj = 1, Xj finite, implying A = 2, and Xj infinite, implying A > 2. The Nelson-Toner anisotropic analysis [19] predicts A = 2. All options imply either a strong anisotropy (A = > 2 or no anisotropy at all A = = 1. Experimentally, a weak anisotropy... [Pg.188]


See other pages where Additive anisotropic is mentioned: [Pg.172]    [Pg.306]    [Pg.6543]    [Pg.178]    [Pg.507]    [Pg.342]    [Pg.53]    [Pg.242]    [Pg.6542]    [Pg.322]    [Pg.284]    [Pg.2816]    [Pg.1006]    [Pg.730]    [Pg.162]   
See also in sourсe #XX -- [ Pg.117 ]




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