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A Six-Pulse PASS MAS-NMR Technique Solved by a Phasor Method
1Condensed Matter and Surface Sciences Program, Ohio University, Athens, Ohio, 45701
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|June 20, 1998
Summary
Phase Adjusted Spinning Sidebands (PASS) MAS-NMR recovers full spectral intensities by phase adjusting spinning sidebands. This six-pulse technique enhances flexibility and resolves pulse overlap issues in solid-state NMR spectroscopy.
Area of Science:
- Solid-state Nuclear Magnetic Resonance (NMR) Spectroscopy
- Materials Science
Background:
- Phase Adjusted Spinning Sidebands (PASS) MAS-NMR is a technique used to recover spectral intensities.
- The original PASS sequence by Dixon utilized four pi pulses.
Purpose of the Study:
- To present a modified PASS MAS-NMR technique using six pi pulses.
- To address limitations of the original PASS sequence, such as pulse overlap and receiver dead-time.
Main Methods:
- Development of a six-pi-pulse PASS MAS-NMR sequence.
- Solving nonlinear, underdetermined PASS equations using a graphical phasor method.
- Testing of all developed PASS sequences.
Main Results:
- The modified PASS MAS-NMR technique successfully recovers full intensities of central resonances by phase adjusting spinning sidebands.
- The six-pi-pulse sequence offers increased flexibility in pulse spacing, eliminating pulse overlap and receiver dead-time.
- A table detailing six-pulse delay times for various pitches is provided.
Conclusions:
- The enhanced six-pi-pulse PASS MAS-NMR technique is effective for recovering spectral intensities in solid-state NMR.
- This method provides a more robust solution for spectral analysis by overcoming previous technical limitations.
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