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  2. Proton nuclear magnetic resonance - Wikipedia

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

    Proton nuclear magnetic resonance (proton NMR, hydrogen-1 NMR, or 1 H NMR) is the application of nuclear magnetic resonance in NMR spectroscopy with respect to hydrogen-1 nuclei within the molecules of a substance, in order to determine the structure of its molecules. [1]

  3. Magnetic inequivalence - Wikipedia

    en.wikipedia.org/wiki/Magnetic_inequivalence

    A classic example is the 1 H-NMR spectrum of 1,1-difluoroethylene. [5] The single 1 H-NMR signal is made complex by the 2 J H-H and two different 3 J H-F splittings. The 19 F-NMR spectrum will look identical. The other two difluoroethylene isomers give similarly complex spectra. [6]

  4. Aromatic ring current - Wikipedia

    en.wikipedia.org/wiki/Aromatic_ring_current

    A diagram of an aromatic ring current. B 0 is the applied magnetic field, the red arrow indicating its direction. The orange ring shows the direction of the ring current, and the purple rings show the direction of the induced magnetic field. An aromatic ring current is an effect observed in aromatic molecules such as benzene and naphthalene.

  5. 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 ...

  6. Nuclear magnetic resonance spectroscopy - Wikipedia

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

    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 ...

  7. Isotopic analysis by nuclear magnetic resonance - Wikipedia

    en.wikipedia.org/wiki/Isotopic_analysis_by...

    As for the wine or the fruit, the interpretation of results in terms of origin is done by comparison of the isotopic parameters of the sample analyzed with those from a group of referenced molecules of known origin. It appears that all the origins of vanillin are well discriminated using 2 H-NMR data. Particularly, vanillin ex-bean can well be ...

  8. Nuclear magnetic resonance spectra database - Wikipedia

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

    SDBS includes 14700 1 H NMR spectra and 13000 13 C NMR spectra as well as FT-IR, Raman, ESR, and MS data. The data are stored and displayed as an image of the processed data. Annotation is achieved by a list of the chemical shifts correlated to letters which are also used to label a molecular line drawing.

  9. Triple-resonance nuclear magnetic resonance spectroscopy

    en.wikipedia.org/wiki/Triple-resonance_nuclear...

    Triple resonance experiments are a set of multi-dimensional nuclear magnetic resonance spectroscopy (NMR) experiments that link three types of atomic nuclei, most typically consisting of 1 H, 15 N and 13 C. These experiments are often used to assign specific resonance signals to specific atoms in an isotopically-enriched protein.