# EUROISMAR 2019

25-30 August 2019
Henry Ford Building
Europe/Berlin timezone

## Solid-state NMR strategies towards speed and resolution

29 Aug 2019, 11:30
25m
Lecture Hall D (Henry Ford Building)

### Lecture Hall D

#### Henry Ford Building

Talk Solid-state NMR development and applications

### Speaker

Ms Kshama Sharma (TIFR Centre for Interdisciplinary Sciences)

### Description

Solid-state NMR is a very flexible and powerful technique for the elucidation of geometry and dynamics information on a variety of samples. However, there is still a need to overcome sensitivity and resolution aspects along with the necessity to carry out multidimensional experiments in a short span of time. In order to overcome these challenges, we have made use of two approaches.

First approach involves the improvement of heteronuclear spin decoupling efficiency at high magic-angle spinning (MAS) frequencies. For this, a unified strategy of two-pulse based heteronuclear decoupling for high-spinning frequencies and low-power radio-frequency irradiation in solid-state MAS NMR is presented which incorporates simultaneous time and phase modulation. Decoupling sequences like TPPM, XiX and rCW turn out to be specific solution of this approach. This approach not only highlights the existing solutions but also generates new solutions for efficient decoupling.

Secondly, to speed up the data acquisition process, process, pulse sequences that implement sequential acquisition strategies on one and two radio radiofrequency channels with a combination of proton and carbon detection to record multiple experiments under MAS have been coded. These strategies are expected to work better with $^{1}$H detection under fast-magic angle spinning due to low RF amplitude requirements. $^{1}$H detection under fast MAS regime demands heteronuclear decoupling on $^{13}$C or $^{15}$N channel in order to achieve the maximum resolution. We show that the longitudinal $^{15}$N polarisation survives decoupling and can be used to perform multiple sequential experiments at fast MAS. Using multiplex phase cycling, we carried out numerous residue linking experiments in a single experimental block that is alone sufficient for obtaining assignments.

### Primary authors

Ms Kshama Sharma (TIFR Centre for Interdisciplinary Sciences) Dr Asif Equbal (UC Santa Barbara) Prof. Nielsen Niels. C. (Aarhus Univeristy, Denmark) Dr Kaustubh R. Mote (TIFR Centre for Interdisciplinary Sciences) Prof. Madhu P. K. (TIFR Centre for Interdisciplinary Sciences)

### Presentation Materials

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