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Quadrupolar Carr—Purcell—Meiboom—Gill QCPMG

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. ... [Pg.112]

QCPMG quadrupolar Carr-Purcell-Meiboom-Gill... [Pg.27]

Site populations in Al2Si205 kyanite and short range order parameters in CaAl2Si20g anorthite have been determined by using Al MQMAS NMR with quadrupolar Carr-Purcell-Meiboom-Gill echo train and FAM-II triple quantum to single quantum conversion pulses (MQ-QCPMG-MAS NMR). " ... [Pg.320]

As a biologically relevant example of solid-state NMR on quadrupolar nuclei. Fig, 11 shows experimental and simulated Zn solid-state NMR spectra of zinc diimidazole diacetate which may be considered a model compound for Zn in metalloproteins. The experimental spectrum was obtained by sampling the FID in between the refocusing pulses in a quadrupolar version of the Carr-Purcell-Meiboom-Gill experiment (QCPMG), 5 In this manner, the hundred kHz wide second-order quadrupolar powder pattern is split into a manifold of spin-echo sidebands with the consequence of highly... [Pg.276]

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. ... [Pg.66]

See other pages where Quadrupolar Carr—Purcell—Meiboom—Gill QCPMG is mentioned: [Pg.141]    [Pg.79]    [Pg.21]    [Pg.103]    [Pg.105]    [Pg.134]    [Pg.18]    [Pg.104]    [Pg.149]    [Pg.275]    [Pg.112]    [Pg.274]    [Pg.313]    [Pg.134]    [Pg.240]    [Pg.141]    [Pg.79]    [Pg.21]    [Pg.103]    [Pg.105]    [Pg.134]    [Pg.18]    [Pg.104]    [Pg.149]    [Pg.275]    [Pg.112]    [Pg.274]    [Pg.313]    [Pg.134]    [Pg.240]    [Pg.39]    [Pg.292]    [Pg.97]    [Pg.115]    [Pg.66]    [Pg.68]   
See also in sourсe #XX -- [ Pg.141 ]



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Carr-Purcell

Carr-Purcell-Meiboom-Gill

Carre

Purcell

Quadrupolar

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