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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. 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.

  4. Nuclear magnetic resonance spectra database - Wikipedia

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

    Available through Wiley Online Library [3] (John Wiley & Sons), SpecInfo on the Internet NMR is a collection of approximately 440,000 NMR spectra (organized as 13 C, 1 H, 19 F, 31 P, and 29 Si NMR databases). The data are accessed via the Internet using a Java interface and are stored in a server developed jointly with BASF. The software ...

  5. 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 ...

  6. Heteronuclear single quantum coherence spectroscopy

    en.wikipedia.org/wiki/Heteronuclear_single...

    The HSQC experiment is a highly sensitive 2D-NMR experiment and was first described in a 1 H— 15 N system, but is also applicable to other nuclei such as 1 H— 13 C and 1 H— 31 P. The basic scheme of this experiment involves the transfer of magnetization on the proton to the second nucleus, which may be 15 N, 13 C or 31 P, via an INEPT ...

  7. Nuclear magnetic resonance decoupling - Wikipedia

    en.wikipedia.org/wiki/Nuclear_Magnetic_Resonance...

    There can also be off-resonance decoupling of 1 H from 13 C nuclei in 13 C NMR spectroscopy, where weaker rf irradiation results in what can be thought of as partial decoupling. In such an off-resonance decoupled spectrum, only 1 H atoms bonded to a carbon atom will split its 13 C signal. The coupling constant, indicating a small frequency ...

  8. 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°.

  9. Spectral Database for Organic Compounds - Wikipedia

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

    The 1 H NMR spectra were recorded at a resonance frequency of 400 MHz with a resolution of 0.0625 Hz or at 90 MHz with a resolution of 0.125 Hz. The spectral acquisition was carried out using a flip angle of 22.5 – 30.0 degrees and a pulse repetition time of 30 seconds. [ 4 ]