Spin diffusion describes a situation wherein the individual nuclear
spins
The spins (as in having "the spins")Diane Marie Leiva. ''The Florida State University College of Education''Women's Voices on College Drinking: The First-Year College Experience"/ref> is an adverse reaction of intoxication that causes a state of ...
undergo continuous exchange of energy.
[EPS2:Spin-Diffusion](_blank)
/ref> This permits polarization
Polarization or polarisation may refer to:
Mathematics
*Polarization of an Abelian variety, in the mathematics of complex manifolds
*Polarization of an algebraic form, a technique for expressing a homogeneous polynomial in a simpler fashion by ...
differences within the sample to be reduced on a timescale much shorter than relaxation effects.
Spin diffusion is a process by which magnetization can be exchanged spontaneously between spins. The process is driven by dipolar coupling, and is therefore related to internuclear distances. Spin diffusion has been used to study many structural problems in the past, ranging from domain sizes in polymers and disorder in glassy materials to high-resolution crystal structure determination of small molecules and proteins.
In solid-state nuclear magnetic resonance
Solid-state NMR (ssNMR) spectroscopy is a technique for characterizing atomic level structure in solid materials e.g. powders, single crystals and amorphous samples and tissues using nuclear magnetic resonance (NMR) spectroscopy. The anisotropic pa ...
, spin diffusion plays a major role in Cross Polarization (CP) experiments. As mentioned before, by transferring the magnetization (and thus the population) from nuclei with different values for the spin-lattice relaxation (''T1''), the overall time for the experiment is reduced. Is a very common practice when the sample contains hydrogen. Another desirable effect is that the signal to noise ratio (S/N) is increased until a theoretical factor γA/γB, being γ the gyromagnetic ratio
In physics, the gyromagnetic ratio (also sometimes known as the magnetogyric ratio in other disciplines) of a particle or system is the ratio of its magnetic moment to its angular momentum, and it is often denoted by the symbol , gamma. Its SI u ...
.
Notes
Quantum field theory
Nuclear magnetic resonance
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