Abstract

The phenomenological Bloch equations in nuclear magnetic resonance are generalized by the addition of terms due to the transfer of magnetization by diffusion. The revised equations describe phenomena under conditions of inhomogeneity in magnetic field, relaxation rates, or initial magnetization. As an example the equations are solved in the case of the free precession of magnetic moment in the presence of an inhomogeneous magnetic field following the application of a 90\ifmmode^\circ\else\textdegree\fi{} pulse with subsequent applications of a succession of 180\ifmmode^\circ\else\textdegree\fi{} pulses. The spin-echo amplitudes agree with the results of Carr and Purcell from a random walk theory.

Keywords

Bloch equationsPhysicsMagnetizationPrecessionCondensed matter physicsRelaxation (psychology)Magnetic fieldLarmor precessionDiffusionSpin (aerodynamics)Magnetization transferAmplitudeMagnetic momentQuantum mechanicsMagnetic resonance imaging

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Publication Info

Year
1956
Type
article
Volume
104
Issue
3
Pages
563-565
Citations
1164
Access
Closed

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H. C. Torrey (1956). Bloch Equations with Diffusion Terms. Physical Review , 104 (3) , 563-565. https://doi.org/10.1103/physrev.104.563

Identifiers

DOI
10.1103/physrev.104.563