Direct magnetic relaxation

In contrast to the above origins of linewidth broadening, which were time independent, the fluctuation of the internal magnetic field direction (magnetic relaxation) may also broaden the y-ray resonance. It was shown... 

Cvi is the number of vinyl groups per chain. The direct observation of the decrease in amplitude of the Fourier Transform-Infrared spectroscopy (FT-IR) spectrum of vinyl groups leads to a square root dependence of a(t) on time. The threshold of gelation occurs at a time t0 such that e(t0) is equal to zero. Again, the magnetic relaxation rate is a function of the variable, e (Figure 8.4). 

The angular velocity and angular momentum acfs themselves are important to any dynamical theory of molecular liquids but are very difficult to extract directly from spectral data. The only reliable method available seems to be spin-rotation nuclear magnetic relaxation. (An approximate method is via Fourier transformation of far-infrared spectra.) The simulated torque-on acfs in this case become considerably more oscillatory, and, which is important, the envelope of its decay becomes longer-lived as the field strength increases. This is dealt with analytically in Section III. In this case, computer simulation is particularly useful because it may be used to complement the analytical theory in its search for the forest among the trees. Results such as these for autocorrelation functions therefore supplement our... 

The spherical harmonic analysis so far presented for uniaxial anisotropy is mainly concerned with the relaxation in a direction parallel to the easy axis of the uniaxial anisotropy. We have not considered in detail the behavior resulting from the transverse application of an external field and the relaxation in that direction for uniaxial anisotropy. Thus we have only considered potentials of the form V(r, t) = V(i, t) where the azimuthal or dependence in Brown s equation is irrelevant to the calculation of the relaxation times. This has simplified the reduction of that equation to a set of differential-difference equations. In this section we consider the reduction when the azimuthal dependence is included. This is of importance in the transition of the system from magnetic relaxation to ferromagnetic resonance. The original study [17] was made using the method of separation of variables on Brown s equation which reduced the solution to an eigenvalue problem. We reconsider the solution by casting... 

The main mechanism for the relaxation of 15N nuclei with directly bonded protons is the hMH dipolar interaction. Under the extreme spectral narrowing condition, (coN + ooH) tc 1, where raN and raH are corresponding resonance frequencies, the nuclear magnetic relaxation is given by ... 

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