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  2. Nuclear magnetic resonance spectroscopy - Wikipedia

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

    A 900 MHz NMR instrument with a 21.1 T magnet at HWB-NMR, Birmingham, UK. Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique based on re-orientation of atomic nuclei with non-zero nuclear spins in an external magnetic field.

  3. Nuclear magnetic resonance crystallography - Wikipedia

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

    Nuclear magnetic resonance crystallography (NMR crystallography) is a method which utilizes primarily NMR spectroscopy to determine the structure of solid materials on the atomic scale. Thus, solid-state NMR spectroscopy would be used primarily, possibly supplemented by quantum chemistry calculations (e.g. density functional theory ), [ 1 ...

  4. Nuclear magnetic resonance - Wikipedia

    en.wikipedia.org/wiki/Nuclear_magnetic_resonance

    Bruker 700 MHz nuclear magnetic resonance (NMR) spectrometer. Nuclear Magnetic Resonance (NMR) basic principles. Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are disturbed by a weak oscillating magnetic field (in the near field [1]) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic ...

  5. Quantum mechanics of nuclear magnetic resonance (NMR ...

    en.wikipedia.org/wiki/Quantum_mechanics_of...

    Nuclear magnetic resonance (NMR) spectroscopy uses the intrinsic magnetic moment that arises from the spin angular momentum of a spin-active nucleus. [1] If the element of interest has a nuclear spin that is not zero, [1] the nucleus may exist in different spin angular momentum states, where the energy of these states can be affected by an external magnetic field.

  6. Paramagnetic nuclear magnetic resonance spectroscopy

    en.wikipedia.org/wiki/Paramagnetic_nuclear...

    The difference between the chemical shift of a given nucleus in a diamagnetic vs. a paramagnetic environment is called the hyperfine shift.In solution the isotropic hyperfine chemical shift for nickelocene is −255 ppm, which is the difference between the observed shift (ca. −260 ppm) and the shift observed for a diamagnetic analogue ferrocene (ca. 5 ppm).

  7. 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 ...

  8. Proton nuclear magnetic resonance - Wikipedia

    en.wikipedia.org/wiki/Proton_nuclear_magnetic...

    Example 1 H NMR spectrum (1-dimensional) of a mixture of menthol enantiomers plotted as signal intensity (vertical axis) vs. chemical shift (in ppm on the horizontal axis). Signals from spectrum have been assigned hydrogen atom groups (a through j) from the structure shown at upper left.

  9. Isotopic shift - Wikipedia

    en.wikipedia.org/wiki/Isotopic_shift

    H NMR spectrum of a solution of HD (labeled with red bars) and H 2 (blue bar). The 1:1:1 triplet arises from the coupling of the 1 H nucleus (I = 1/2) to the 2 H nucleus (I = 1). In NMR spectroscopy, isotopic effects on chemical shifts are typically small, far less than 1 ppm, the typical unit for measuring shifts. The 1 H NMR signals for 1 H 2 ...