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Insensitive nuclei enhancement by polarization transfer (INEPT) is a signal enhancement method used in NMR spectroscopy. It involves the transfer of nuclear spin polarization from spins with large Boltzmann population differences to nuclear spins of interest with lower Boltzmann population differences. [ 1 ]
Graphical representation of the INEPT NMR pulse sequence. INEPT is utilized often to improve 15 N resolution because it can accommodate negative gyromagnetic ratios, increases Boltzmann polarization, and decreases T 1 relaxation. [3] Insensitive nuclei enhanced by polarization transfer (INEPT) is a signal
The linewidth is optimized for polarization transfer from electrons to nuclei, when it is close to the nuclear Larmor frequency. The optimization is related to an embedded three-spin (electron-electron-nucleus) process that mutually flips the coupled three spins under the energy conservation (mainly) of the Zeeman interactions.
The nuclear Overhauser effect (NOE) is the transfer of nuclear spin polarization from one population of spin-active nuclei (e.g. 1 H, 13 C, 15 N etc.) to another via cross-relaxation.
Considering these techniques from the opposite perspective, that magnetization (i.e. spin polarization) is being transferred from the bulk water to the spin-saturated hydration population, allows one to conceptually unify chemical exchange methods with other techniques that transfer magnetization between nuclei populations.
CIDNP (chemically induced dynamic nuclear polarization), often pronounced like "kidnip", is a nuclear magnetic resonance (NMR) technique that is used to study chemical reactions that involve radicals. It detects the non-Boltzmann (non-thermal) nuclear spin state distribution produced in these reactions as enhanced absorption or emission signals.
Finally, the free induction decay (FID) of the X nuclei is detected, typically with 1 H decoupling. Cross-polarization ( CP ), originally published as nuclear double resonance in the rotating frame by Hartmann and Hahn [ 1 ] is a solid-state nuclear magnetic resonance (ssNMR) technique used to transfer nuclear magnetization from different types ...
The IBM2/IBM-II model treats protons and neutrons separately. Both models are restricted to nuclei with even numbers of protons and neutrons. [1]: 9 Regions of differently shaped nuclei, as predicted by the Interacting Boson Approximation [2] The model can be used to predict vibrational and rotational modes of non-spherical nuclei. [2]