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  2. 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.

  3. Paramagnetic nuclear magnetic resonance spectroscopy

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

    Paramagnetism diminishes the resolution of an NMR spectrum to the extent that coupling is rarely resolved. Nonetheless spectra of paramagnetic compounds provide insight into the bonding and structure of the sample. For example, the broadening of signals is compensated in part by the wide chemical shift range (often 200 ppm in 1 H NMR).

  4. 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.

  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 of stereoisomers

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

    Mosher's acid contains a -CF 3 group, so if the adduct has no other fluorine atoms, the 19 F NMR of a racemic mixture shows just two peaks, one for each stereoisomer. As with NMR spectroscopy in general, good resolution requires a high signal-to-noise ratio , clear separation between peaks for each stereoisomer, and narrow line width for each peak.

  7. Two-dimensional nuclear magnetic resonance spectroscopy

    en.wikipedia.org/wiki/Two-dimensional_nuclear...

    The spectrum that appears along both the horizontal and vertical axes is a regular one dimensional 1 H NMR spectrum. The bulk of the peaks appear along the diagonal, while cross-peaks appear symmetrically above and below the diagonal. COSY-90 is the most common COSY experiment. In COSY-90, the p1 pulse tilts the nuclear spin by 90°.

  8. Isotopic analysis by nuclear magnetic resonance - Wikipedia

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

    Figure 5 -Steps of SNIF-NMR of ethanol - Official method. The SNIF-NMR is applied on pure (or purified) molecules. Therefore, some preparation steps may be required in the lab before analysis. For example, for the SNIF-NMR of ethanol, according to official methods: Fermentation (for fruit juice) Quantitative extraction of ethanol by distillation

  9. 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 ...