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  2. Magnetic dipole–dipole interaction - Wikipedia

    en.wikipedia.org/wiki/Magnetic_dipole–dipole...

    Magnetic dipole–dipole interaction, also called dipolar coupling, refers to the direct interaction between two magnetic dipoles.Roughly speaking, the magnetic field of a dipole goes as the inverse cube of the distance, and the force of its magnetic field on another dipole goes as the first derivative of the magnetic field.

  3. Residual dipolar coupling - Wikipedia

    en.wikipedia.org/wiki/Residual_dipolar_coupling

    For a fully oriented molecule, the dipolar coupling for an 1 H-15 N amide group would be over 20 kHz, and a pair of protons separated by 5 Å would have up to ~1 kHz coupling. However the degree of alignment achieved by applying magnetic field is so low that the largest 1 H-15 N or 1 H-13 C dipolar couplings are <5 Hz. [19]

  4. Solid-state nuclear magnetic resonance - Wikipedia

    en.wikipedia.org/wiki/Solid-state_nuclear...

    Solid-state 900 MHz (21.1 T [1]) NMR spectrometer at the Canadian National Ultrahigh-field NMR Facility for Solids. Solid-state nuclear magnetic resonance (ssNMR) is a spectroscopy technique used to characterize atomic-level structure and dynamics in solid materials. ssNMR spectra are broader due to nuclear spin interactions which can be categorized as dipolar coupling, chemical shielding ...

  5. J-coupling - Wikipedia

    en.wikipedia.org/wiki/J-coupling

    Example 1 H NMR spectrum (1-dimensional) of ethanol plotted as signal intensity vs. chemical shift.There are three different types of H atoms in ethanol regarding NMR. The hydrogen (H) on the −OH group is not coupling with the other H atoms and appears as a singlet, but the CH 3 − and the −CH 2 − hydrogens are coupling with each other, resulting in a triplet and quartet respectively.

  6. Relaxation (NMR) - Wikipedia

    en.wikipedia.org/wiki/Relaxation_(NMR)

    In conventional NMR spectroscopy, T 1 limits the pulse repetition rate and affects the overall time an NMR spectrum can be acquired. Values of T 1 range from milliseconds to several seconds, depending on the size of the molecule, the viscosity of the solution, the temperature of the sample, and the possible presence of paramagnetic species (e.g ...

  7. Nuclear magnetic resonance spectroscopy of proteins - Wikipedia

    en.wikipedia.org/wiki/Nuclear_magnetic_resonance...

    The dipolar coupling is commonly used in solid state NMR and provides information about the relative orientation of the bond vectors relative to a single global reference frame. Typically the orientation of the N-H vector is probed in an HSQC-like experiment. Initially, residual dipolar couplings were used for refinement of previously ...

  8. Magnetization transfer - Wikipedia

    en.wikipedia.org/wiki/Magnetization_transfer

    The mechanisms of nuclear-spin energy-coupling have been extensively characterized and are described in the following articles: Angular momentum coupling, Magnetic dipole–dipole interaction, J-coupling, Residual dipolar coupling, Nuclear Overhauser effect, Spin–spin relaxation, and Spin saturation transfer. Alternatively, some nuclei in a ...

  9. Nuclear Overhauser effect - Wikipedia

    en.wikipedia.org/wiki/Nuclear_Overhauser_effect

    The dipolar mechanism is the only common relaxation mechanism that can cause transitions in which more than one spin flips. Specifically, the dipolar relaxation mechanism gives rise to transitions between the αα and ββ states ( W 2 ) and between the αβ and the βα states ( W 0 ).