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1.8: What is the tip angle?

  • Page ID
    77763
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    The angle that the B1 pulse tips the magnetization through depends on the power of the pulse and its length. For a given power setting, a tip angle, θ, (in radians) can be defined as θ = γB1τ, where γ is the magnetogyric ratio and τ is the length of time the pulse is on. What we detect in the NMR experiment is the projection of the macroscopic magnetization vector, Mxy, into the xy plane of the NMR coordinate system. A 90o pulse will produce the greatest signal in the xy plane. The Figure below shows the effect of a 90o pulse on the spins.

    tip_angle.PNG


    This page titled 1.8: What is the tip angle? is shared under a CC BY-NC-SA 2.5 license and was authored, remixed, and/or curated by Cynthia K. Larive & Albert K. Korir via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.