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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.
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 ...
In conventional NMR spectroscopy, T 1 limits the pulse repetition rate and affects the overall time an NMR spectrum can be acquired. Values of T 1 range from milliseconds to several seconds, depending on the size of the molecule, the viscosity of the solution, the temperature of the sample, and the possible presence of paramagnetic species (e.g ...
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.
The Karplus equation, named after Martin Karplus, describes the correlation between 3 J-coupling constants and dihedral torsion angles in nuclear magnetic resonance spectroscopy: [2] J ( ϕ ) = A cos 2 ϕ + B cos ϕ + C {\displaystyle J(\phi )=A\cos \,2\phi +B\cos \,\phi +C}
Free induction decay (FID) nuclear magnetic resonance signal seen from a well shimmed sample. In Fourier transform nuclear magnetic resonance spectroscopy, free induction decay (FID) is the observable nuclear magnetic resonance (NMR) signal generated by non-equilibrium nuclear spin magnetization precessing about the magnetic field (conventionally along z).
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 zero, [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.
In NMR spectroscopy, the Solomon equations describe the dipolar relaxation process of a system consisting of two spins. [1] They take the form of the following ...