Increased resolution in MAS NMR spectra by two-dimensional separation of sidebands by order

Recent Advances in Solid‐State MAS NMR Methodology for Probing Structure and Dynamics in Polymeric and Supramolecular Systems

“…(Reproduced from ref. [228] ) PATROS (PASS-t r -ODESSA) experiment, the time-reversed ODESSA experiment is combined with the 2D-PASS ( phaseadjusted spinning sidebands) experiment, [231,232] so as to separate overlapping sideband manifolds according to their order in a second frequency dimension. [233] In the CODEX (centreband-only detection of exchange) experiment, [234,235] there is no analysis of spinning sidebands, instead changes in the intensity of the centreband are monitored in an experiment that sandwiches an exchange period between two CSA recoupling sequences.…”

A Six-Pulse PASS MAS-NMR Technique Solved by a Phasor Method

“…Also in the area of glasses (e.g., Se type glasses (14)), long T 1 times of 15 min or more produce lengthy experiments. In those cases a 2D TOSS experiment increases the duration of data acquisition by a factor n, where n is the number of sidebands that need to be recovered (11). In contrast, PASS only requires two spectra to recover all even and all uneven sidebands, three spectra to recover all sidebands modulo 3, etc.…”

“…PASS is recommended for systems with short T 2 times, long T 1 times, and for experiments with long data acquisition. The newer 2D TOSS sequences (11,12) are the two-dimensional analogue to PASS. They have the advantage that pure absorptive sideband lineshapes are obtained.…”

PATROS—A New MAS Exchange Method Using Sideband Separation: Application to Poly(n-butylmethacrylate)

“…Such a sequence is the PASS (Phase Adjusted Spinning Sidebands) originally proposed by Dixon (20,39) and subsequently modified and extended to two-dimensions by Spiess and co-workers (22,23) and by Levitt and co-workers (24 -27). The PASS pulse sequence is shown in Fig.…”