Sideband Patterns from Rotor-Encoded Longitudinal Magnetization in MAS Recoupling Experiments

Advanced 1H Solid‐State NMR Spectroscopy on Hydrogels, 1

“…Conversely, the intensity of such ''unwanted'' sidebands allows the validity of the spin-pair approach to be estimated. It has been demonstrated by experiments [22] and theoretical simulations [26] that for hydrogen-bonded dimers of carboxylic acids the situation can be safely approximated by neglecting the weak even-order sidebands and considering only the intensities of the odd-order ones, thus assuming an isolated 1 H-1 H pair.…”

Recoupled Polarization-Transfer Methods for Solid-State 1H–13C Heteronuclear Correlation in the Limit of Fast MAS

“…In a recent paper, we have shown that in a slightly modified experiment (involving an initial CP), longitudinal magnetization (e.g., as created from the cosine term in Eq. [6]) can also be rotor-encoded to yield sideband patterns which are dominated by even-order sidebands (34).…”

REDOR-Based Heteronuclear Dipolar Correlation Experiments in Multi-Spin Systems: Rotor-Encoding, Directing, and Multiple Distance and Angle Determination

“…(6) for the case of N rcpl ¼ 2 (b). The middle trace in (b) corresponds to a sideband pattern generated by HDOR experiments [11], while the upper trace corresponds to a RELM pattern [24]. The calculations are based on a coupling constant of 23 kHz and o R =2p ¼ 30 kHz:…”

“…The sin-sin term corresponds to the modulation associated with the two-spin terms in the HSQC, HMQC, and HDOR varieties [12], while the cos-cos term corresponds to the single-spin modulation detected in the RELM experiment [24]. The former term leads to a spinning-sideband pattern with odd-order sidebands only, while the latter term leads to even-order sidebands only.…”

“…In our recent publications [11][12][13]24], heteronuclear single-quantum correlation (HSQC, which involves antiphase magnetization in t 1 ; see also Fig. 2) and heteronuclear multiple-quantum correlation (HMQC) were the methods of choice for shift correlation experiments, while heteronuclear dipolar-order rotor encoding (HDOR) and rotor-encoding of longitudinal magnetization (RELM) were used for efficient measurement of the RRE spinning-sideband patterns.…”