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Efficiency factor- nucleus. H o. Alignment. Energy. parallel. D E = h g H o. Constants. Strength of magnet. anti-parallel. Spin ½ Nuclei in Magnetic Fields Occupy One of Two Energy States. Two spins. All spins Sum. Bulk Magnetization. excess facing down.
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Efficiency factor- nucleus Ho Alignment Energy parallel DE = h g Ho Constants Strength of magnet anti-parallel Spin ½ Nuclei in Magnetic Fields Occupy One of Two Energy States
Two spins All spins Sum Bulk Magnetization excess facing down The Classical Treatment:Nuclear Spin Angular Momentum Ho parallel anti-parallel • Torque + int. motion = precession • Precession around Z axis • Larmor frequency (): DE = hgHo DE = hn n/2P = B0 =
Pulse Fourier Transform NMR t 90ºx RF pulse = = H0 Ho Ho A t Fourier Transform f Variation of signal at X axis vs. time NMR frequency
The Power of Fourier Transform t 90ºx RF pulse + 1 = H0 2 = H0 A t Fourier Transform f 2 1 • NMR frequency domain • Spectrum of frequencies • NMR time domain • Variation in amplitude vs time