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  2. Bloch equations - Wikipedia

    en.wikipedia.org/wiki/Bloch_equations

    In physics and chemistry, specifically in nuclear magnetic resonance (NMR), magnetic resonance imaging (MRI), and electron spin resonance (ESR), the Bloch equations are a set of macroscopic equations that are used to calculate the nuclear magnetization M = (M x, M y, M z) as a function of time when relaxation times T 1 and T 2 are present.

  3. 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 0, [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.

  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. 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. Relaxation (NMR) - Wikipedia

    en.wikipedia.org/wiki/Relaxation_(NMR)

    Solomon equations are used to calculate the transfer of magnetization as a result of relaxation in a dipolar system. They can be employed to explain the nuclear Overhauser effect , which is an important tool in determining molecular structure.

  7. 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).

  8. Nuclear magnetic resonance spectroscopy of proteins

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

    Protein NMR utilizes multidimensional nuclear magnetic resonance experiments to obtain information about the protein. Ideally, each distinct nucleus in the molecule experiences a distinct electronic environment and thus has a distinct chemical shift by which it can be recognized. However, in large molecules such as proteins the number of ...

  9. Instrumental chemistry - Wikipedia

    en.wikipedia.org/wiki/Instrumental_chemistry

    Hyphenated techniques are widely used in chemistry and biochemistry. A slash is sometimes used instead of hyphen, especially if the name of one of the methods contains a hyphen itself. Examples of hyphenated techniques: Gas chromatography-mass spectrometry (GC-MS) Liquid chromatography–mass spectrometry (LC-MS)