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  2. Relaxation (NMR) - Wikipedia

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

    The form of the spectral density functions depend on the physical system, but a simple approximation called the BPP theory is widely used. Another relaxation mechanism is the electrostatic interaction between a nucleus with an electric quadrupole moment and the electric field gradient that exists at the nuclear site due to surrounding charges ...

  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. Spectral density - Wikipedia

    en.wikipedia.org/wiki/Spectral_density

    The spectral centroid of a signal is the midpoint of its spectral density function, i.e. the frequency that divides the distribution into two equal parts. The spectral edge frequency ( SEF ), usually expressed as "SEF x ", represents the frequency below which x percent of the total power of a given signal are located; typically, x is in the ...

  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. Two-dimensional nuclear magnetic resonance spectroscopy

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

    While 1D NMR is more straightforward and ideal for identifying basic structural features, COSY enhances the capabilities of NMR by providing deeper insights into molecular connectivity. The two-dimensional spectrum that results from the COSY experiment shows the frequencies for a single isotope, most commonly hydrogen (1 H) along both axes.

  7. Spectral line shape - Wikipedia

    en.wikipedia.org/wiki/Spectral_line_shape

    Spectral line shape or spectral line profile describes the form of an electromagnetic spectrum in the vicinity of a spectral line – a region of stronger or weaker intensity in the spectrum. Ideal line shapes include Lorentzian , Gaussian and Voigt functions, whose parameters are the line position, maximum height and half-width. [ 1 ]

  8. 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 ...

  9. Relaxometry - Wikipedia

    en.wikipedia.org/wiki/Relaxometry

    Apparatus and technological support of the method is constantly developed. An NMR relaxometer is a device for relaxation time measuring. Laboratory NMR relaxometers for NMR signal registration are available in small sizes. [3] In NMR relaxometry (NMRR) only one specific NMRR parameter is measured, not the whole spectrum (which is not always ...