Indirect high-resolution detection for quadrupolar spin-3/2 nuclei in dipolar HMQC solid-state NMR experiments

Trébosc, Julien; Lafon, Olivier; Hu, Bingwen; Amoureux, Jean‐Paul

doi:10.1016/j.cplett.2010.07.037

Cited by 33 publications

(15 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…40,[55][56][57] More recently, its broadbandedness has also been exploited for the detection of correlations to ultra-wideline and isotropic spectra of heavy spin-1/2 nuclei 58,59 as well as satellite transitions of quadrupolar nuclei. 60,61 Despite the abovementioned advantages, the D-RINEPT and D-HMQC techniques are limited by the lack of radiofrequency (RF) power flexibility of non-γ-encoded heteronuclear dipolar recoupling sequences. While a near continuum of γ-encoded heteronuclear recoupling sequences (that also decouple homonuclear dipolar interactions) exists with both high-and lowradiofrequency (RF) requirements, non-γ-encoded heteronuclear dipolar recoupling sequences are limited to low RF power (νRF = 2νR or 4/3νR, where νR denotes the MAS spinning frequency).…”

Section: Introductionmentioning

confidence: 99%

Enhanced 1H-X D-HMQC performance through improved 1H homonuclear decoupling

Perras

Goh

Wang

et al. 2019

Solid State Nuclear Magnetic Resonance

View full text Add to dashboard Cite

The sensitivity of solid-state NMR experiments that utilize 1H zero-quantum heteronuclear dipolar recoupling, such as D-HMQC, is compromised by poor homonuclear decoupling. This leads to a rapid decay of recoupled magnetization and an inefficient recoupling of long-range dipolar interactions, especially for nuclides with low gyromagnetic ratios. We investigated the use, in symmetry-based 1H heteronuclear recoupling sequences, of a basic R element that was principally designed for efficient homonuclear decoupling. By shortening the time required to suppress the effects of homonuclear dipolar interactions to the duration of a single inversion pulse, spin diffusion was effectively quenched and long-lived recoupled coherence lifetimes could be obtained. We show, both theoretically and experimentally, that these modified sequences can yield considerable sensitivity improvements over the current state-of-the-art methods and applied them to the indirect detection of 89Y in a metal-organic framework.

show abstract

Section: Introductionmentioning

confidence: 99%

Enhanced 1H-X D-HMQC performance through improved 1H homonuclear decoupling

Perras

Goh

Wang

et al. 2019

Solid State Nuclear Magnetic Resonance

View full text Add to dashboard Cite

show abstract

“…Therefore, the quest for increased resolution in the quadrupolar dimension of 2D correlation spectra under MAS has led over the past years to the development of several sequences, which all derive from the alliance of a multiple-quantum (MQ) 11 or satellite transition (ST) 12 MAS quadrupolar filter with one of the above-mentioned HETCOR schemes. These filters were first combined with HETCOR experiments relying either on single coherence transfers, such as classical CP (MQ-CP-HETCOR, [13][14][15] and ST-CP-HETCOR) 16 or J-R-INEPT (MQ-J-R-INEPT), 4,15,17 or on two consecutive coherence transfers, such as the MQ-J-HMQC 18 and HMQC-ST 19 experiments. However, (i) CP transfers involving quadrupolar nuclei suffer from lack of robustness, as mentioned above, 6 (ii) the MQ-J-HMQC experiment requires a prohibitively long 3D acquisition and (iii) HMQC-ST is only applicable to spin-3/2 nuclei (for other spin values, the phase cycling can't separate the interactions).…”

Section: Introductionmentioning

confidence: 99%

“…However, (i) CP transfers involving quadrupolar nuclei suffer from lack of robustness, as mentioned above, 6 (ii) the MQ-J-HMQC experiment requires a prohibitively long 3D acquisition and (iii) HMQC-ST is only applicable to spin-3/2 nuclei (for other spin values, the phase cycling can't separate the interactions). 19 Presently, the most robust high-resolution experiment adapted to quadrupolar nuclei with any halfinteger spin value is thus the MQ-J-R-INEPT sequence. 4,15,17 However, depending on the sample, this J-mediated experiment may present a low signal to noise (S/N) ratio when the signal decay resulting from coherent and incoherent processes is faster than the dephasing under the J coupling.…”

Section: Introductionmentioning

confidence: 99%

High-resolution through-space correlations between spin-1/2 and half-integer quadrupolar nuclei using the MQ-D-R-INEPT NMR experiment

Martineau

Bouchevreau

Taulèlle

et al. 2012

Phys. Chem. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

The multiple-quantum dipolar refocused-INEPT (MQ-D-R-INEPT) NMR experiment is presented. This new pulse sequence allows the generation of two-dimensional through-space NMR correlation spectra between spin-½ and quadrupolar nuclei under high-resolution. Compared to the existing sequences, the MQ-D-R-INEPT sequence benefits from increased robustness, due to the reduced sensitivity to offsets and radio-frequency field inhomogeneity of the R-INEPT recoupling scheme as compared to the classical cross-polarization transfer involving a quadrupolar nucleus, and applicability to quadrupolar nuclei with any half-integer spin value. Here, the heteronuclear dipolar couplings have been reintroduced using the rotary resonance recoupling (R(3)) sequence, chosen because it is γ-encoded, and thus robust to spinning speed instabilities and to radio-frequency inhomogeneities in the case of nuclei subjected to large chemical shift anisotropy (e.g., (31)P). In the course of the article, a new definition of γ-encoding is introduced, more general and practical than the previous ones, as it does not depend on the implementation of the recoupling sequence, and is independent of the considered frame. The efficiency of the MQ-D-R-INEPT experiment is demonstrated for the observation of (31)P-(27)Al proximities. It is first tested on AlPO4-VPI-5, and then applied to a complex aluminophosphate AlPO4-(Al5P7)-DAE of incompletely established structure. For this latter sample, the high-resolution provided by the MQMAS filter allows the resolution of a large number of (31)P-(27)Al correlations, which represent an essential step towards the determination of its structural model.

show abstract

“…The t 1 -noise hampers the observation of 2D D-HMQC and D-HMQC filtered 1D 1 H NMR at 80 kHz. Active synchronization of excitation and reconversion sequence to sample spinning should reduce the t 1 -noise [13,26]. Alternatively, this problem could be solved by continuously notifying the instantaneous spinning frequency and updating the pulse sequence timing.…”

Section: Resultsmentioning

confidence: 98%