Quadrupolar Carr-Purcell Meiboom-Gill pulse sequence

NMR studies of metals in sohd state non-metallic materials such as zeolites, inorganic complexes, glasses, coals, polymers, metalloproteins, and RNA have been reviewed. The role of solid state NMR spectroscopy in investigating the structural and functional aspects of these materials with no long range order is evaluated. This overview presents several developments of solid state NMR to the study of a variety of metal containing materials. In particular, the use of the quadrupolar Carr-Purcell-Meiboom-Gill pulse sequence for the acquisition of solid state NMR spectra of quadrupolar nuclei with low natural abundances and low NMR frequencies, and applications of solid state Cd NMR are covered in detail. 

Carr-Purcell-Meiboom-Gill pulse sequences. The spectra were dominated by the second-order quadrupolar interaction. 

CPMG (Carr-Purcell-Meiboom-Gill) pulse sequence to odd-half-integer quadrupolar spin systems. It was found that QCPMG (controlled CPMG) can be one order of magnitude more sensitive than quadrupolar echo MAS experiments. Assisted by numerical simulation, the QCPMG MAS experiments can be used to determine the quadrupolar as well as chemical shift tensors. ... 

Potassium ( K) (I = 3j2). The quadrupolar Carr-Purcell Meiboom-Gill (QCPMG) and double frequency sweep (DFS)/QCPMG pulse sequences were applied to acquire solid-state NMR spectra of organometallic complexes. The results show there are significant quadrupolar interactions, which depend on temperature, in the polymeric main group metallocenes cyclopenta-dienyl potassium and pentamethylcyclopentadienyl potassium. Sodium and potassium tetraphenylborates were examined by solid-state Na and NMR spectroscopy as mentioned in 2.1.5 Sodium. ... 

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