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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. Spectral Database for Organic Compounds - Wikipedia

    en.wikipedia.org/wiki/Spectral_Database_for...

    If a spectrum of an unknown chemical compound is available, a reverse search can be carried out by entering the values of the chemical shift, frequency or mass of the peaks in the NMR, FT-IR or EI-MS spectrum respectively. This type of search affords all the chemical compounds in the database that have the entered spectral characteristics. [6]

  4. 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).

  5. 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.

  6. 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 ...

  7. 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.

  8. Isotopic analysis by nuclear magnetic resonance - Wikipedia

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

    On the following 2 H-NMR spectrum (Figure 8), a peak corresponds to one of the three observed isotopomers of ethanol. In the AOAC official method, the ratios of (D/H)CH 3 and (D/H)CH 2 are calculated by comparison with an Internal standard, tetramethylurea (TMU), with a certified (D/H) value.

  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 ...