Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Asymmetric parameter

Here, ojr is the rate of spinner rotation. I is the proton spin number, 8 is the chemical shift anisotropy (CSA) and q is the asymmetric parameter of the CSA tensor. Thus, the line broadening occurs when an incoherent fluctuation frequency is very close to the coherent amplitude of proton decoupling monotonously decreased values without such interference in Figure 1. [Pg.12]

We can successfully measure 170 MAS NMR spectra of poly(L-Ala)s using high-field and high-speed magic-angle spinning technique. From the 170 MAS spectra three kinds of NMR parameters such as chemical shift, quadrupolar coupling constant and asymmetric parameter were obtained exactly and understood the relationship... [Pg.133]

Fig. 12. DOR spectra of Na of sodium oxalate, with different spinning speeds. The quadrupolar coupling constant is 405 kHz, the asymmetric parameter is 0.72, and the... Fig. 12. DOR spectra of Na of sodium oxalate, with different spinning speeds. The quadrupolar coupling constant is 405 kHz, the asymmetric parameter is 0.72, and the...
Here. gyromagnetic ratios of the I and S nuclei, respectively, and r is the intemuclear distance between the spins I and S. (Og and (Oj are the carbon resonance frequency and the amplitude of the proton decoupling RF field, respectively. (Or is the rate of spinner rotation, b the chemical shift anisotropy and rj the asymmetric parameter of the chemical shift tensor. [Pg.126]

Electric Hyperfine Interactions Finally we discuss the oscillations of time spectra caused by the nuclear ground-state and excited-state splittings due to electric field gradients (EFGs). We limited our discussion in an axially symmetric EFG (asymmetric parameter tj = 0), and furthermore, the EFG axis is randomly oriented over the space. Then we can get the time spectrum [8] (Fig. 12.2)... [Pg.252]

We investigated the mechanistic memory of the PE 12,000 atoms to reform a sphere-like shape for the Si, C, and Al surfaces by calculating the asymmetric parameter in Eq. (20). As shown in Fig. 32, the particle with the initial velocity 5 A/ps tended to self-organize into the spherical shape during equilibration. Since the particles spread (coats) on the surfaces on impact, the asymmetric parameter had the largest value at the impact (oblate top). It was interesting to note... [Pg.73]

In Figure 7-28(a) is shown the theoretical NMR spectmm in which the asymmetrical parameter(Ti) is 0.5. Peak separations Avj, Av2 and AV3 have different values from each other. If the symmetrical motion takes place, the molecular motion is reflected in the observed spectrum as an axially symmetrical powder pattern. Figure 7-28(b) shows the observed H NMR spectrum of PG-IO-N-D at 40 " C, where N-D means that the main-chain amide proton is substituted by H. The observed spectrum shows a typical powder pattern composed of the inner peaks(Avj), the shoulders(Av2) and the outermost wingsCAvj). Therefore, this means that molecular motion of PG-IO-N-D is restricted at 40 " C. [Pg.163]


See other pages where Asymmetric parameter is mentioned: [Pg.794]    [Pg.126]    [Pg.194]    [Pg.96]    [Pg.91]    [Pg.236]    [Pg.74]    [Pg.578]    [Pg.74]    [Pg.91]    [Pg.87]    [Pg.25]    [Pg.127]    [Pg.220]    [Pg.74]    [Pg.385]    [Pg.151]    [Pg.152]    [Pg.35]   
See also in sourсe #XX -- [ Pg.96 ]




SEARCH



Asymmetric interaction parameters, interface

Asymmetric molecules with asymmetry parameters values

List of tabulated asymmetric-top hfs parameters

© 2024 chempedia.info