The Application of Simple and Easy to Implement Decoupling Pulse Scheme Combinations to Effect Decoupling of LargeJValues with Reduced Artifacts

[摘要] Of the various problems in decoupling one nucleus type from another using standard decoupling pulse schemes for broadband decoupling, a particular challenge is to effect full, artifact-free decoupling when the size of the coupling constant is very large. Herein it is demonstrated that1H decoupling of the31P NMR spectrum of diethyl phosphonate{HP(=O)(OCH2CH3)2}can be accomplished with reduced artifacts despite the largeJH,P1value of 693 Hz by using a combination of decoupling pulse schemes involving continuous-wave (CW) irradiation and either adiabatic-pulse decoupling (APD), MPF decoupling, or traditional composite-pulse decoupling (CPD) schemes such as WALTZ or GARP. The considered strategy is simple, efficient, and easy to implement on most instruments. The best result was attained for a combination of CW and CPD using GARP with a standard pulse width of 60 μs. Altogether, the advantages of the methodology include low power requirements, complete decoupling, tolerance of a range of largeJvalues, large bandwidth for normal-sizedJvalues, and the suppression of sidebands.

[学科分类] 光谱学