## Abstract

A novel view on the presentation of pulsed field-gradient nuclear magnetic resonance experiments to encode position and translational displacements is given. A conventional diffusion or flow experiment employing two magnetic field gradients of effective area k_{1}, and k_{2} separated by a time interval △ can formally be expressed as a means to probe k space in a two-dimensional way. While for most applications, a full coverage of the [k_{1}, k_{2}] space is not necessary, an experiment with k_{1} = -k_{2} can be regarded as a sampling of the secondary diagonal in [k_{1}, k_{2}] space. Likewise, the main diagonal is represented by the condition k_{1} = k_{2} and encodes position. Thus, the [r_{1}, r_{2}] space conjugate to [k_{1}, k_{2}], which is obtained by Fourier transformation, can be transferred into a position/displacement correlation plot simply by rotation of the coordinate system by an angle of 45°. While displacement R = r_{2} - r_{1} corresponds to an average velocity v̄ = R/△, an extension towards higher-order derivations such as acceleration is straightforward by modification of the pulse sequence. We discuss this new concept in a general way, treating both the magnetic field and the particle position by Taylor expansions with respect to space and time, respectively, and present examples for fluid flowing through capillary systems in the light of the suggested interpretation.

Original language | English (US) |
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Pages (from-to) | 101-114 |

Number of pages | 14 |

Journal | Applied Magnetic Resonance |

Volume | 18 |

Issue number | 1 |

DOIs | |

State | Published - 2000 |

## ASJC Scopus subject areas

- Atomic and Molecular Physics, and Optics