Dynamical Decoupling in Water-Glycerol Glasses: A Comparison of Nitroxides, Trityl Radicals and Gadolinium Complexes

Abstract

The manuscript presents a dynamical decoupling study of three EPR spin labels in glassy water-glycerol, corresponding to common experimental conditions for dipolar spectroscopy. The main text and the supporting information (split into part A and B) are uploaded as separate PDF documents and contain all information for interpreting and reproducing the findings.<br>

Intermolecular contributions, filtration effects and signal composition of SIFTER (single-frequency technique for refocusing)

“…3e). This follows from the fact that at τ 1 = 0 or τ 2 = 0 the two terms are equal, while at the time point τ 1 = τ 2 the unscaled term B S (τ 1 , τ 2 ) assumes a larger value than the unscaled term B t (τ 1 )B t (τ 2 ), as is also known from dynamical decoupling (Soetbeer et al, 2021b;Wolfowicz and Morton, 2016;Bahrenberg et al, 2021). In the case when the SIFTER experiment is performed on a frozen solution of monoradicals, there is no intramolecular dipolar term, and the overall SIFTER signal V mono SIFTER (τ 1 , τ 2 ) will consist of the contribution with no intermolecular coherence transfer, which will have the transverse evolution term of the form B S (τ 1 , τ 2 ), and the contribution with intermolecular coherence transfer, which will have the transverse evolution of the form B t (τ 1 )B t (τ 2 ); thus,…”