Frequency- and phase-modulated heteronuclear decoupling in rotating solids.

Z Gan; R R Ernst

doi:10.1016/s0926-2040(96)01294-5

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Frequency- and phase-modulated heteronuclear decoupling in rotating solids.

Z Gan·R R Ernst

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Abstract

The mechanism of heteronuclear dipolar decoupling by the TPPM sequences, proposed by Bennett et al. (J. Chem. Phys. 103 (1995) 6951) is investigated by comparison with a modified pulse sequence, called TPFM, that uses frequency instead of phase modulation. By combining frequency and phase modulations, circularly modulated sequences are designed. The fact that only the left-handed modulation sequence FMPML leads to improved proton decoupling, while the right-handed modulation sequence FMPMR is ineffective, proves that the efficient decoupling is caused by a secondary resonance effect.

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Chemical Phenomena Chemistry, Physical Formates Fourier Analysis Magnetic Resonance Spectroscopy Models, Chemical Protons Radio Waves Rotation Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Z Gan, R R Ernst. 1997. Frequency- and phase-modulated heteronuclear decoupling in rotating solids.. https://doi.org/10.1016/s0926-2040(96)01294-5

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