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  • Comment on “Chirality-Induced Electron Spin Polarization and Enantiospecific Response in Solid-State Cross-Polarization Nuclear Magnetic Resonance”
Title: Comment on “Chirality-Induced Electron Spin Polarization and Enantiospecific Response in Solid-State Cross-Polarization Nuclear Magnetic Resonance”
Recently, Santos et al. published an article titled “Chirality-Induced Electron Spin Polarization and Enantiospecific Response in Solid-State Cross-Polarization Nuclear Magnetic Resonance” in ACS Nano. In this article it was claimed that crystalline amino acid enantiomers can give rise to 1H-15N and 1H-13C cross-polarization magic angle spinning (CPMAS) solid-state NMR spectra with different relative signal intensities. The authors attributed such differences to transient changes in T1 relaxation times resulting from an interaction between the electron spins and the radiofrequency contact pulses used in the CPMAS experiment, and discussed this proposed phenomenon in terms of the chirality-induced spin selectivity (CISS) effect. We disagree with the authors conclusion that the CISS effect plays a role in the different signal intensities observed in the CPMAS solid-state NMR spectra of crystalline enantiomers. Quantitative 13C CPMAS experiments on aspartic acid enantiomers demonstrate that CPMAS signal variations can likely be attributed to sample dependent differences in T1 relaxation times rather than any chirality effects.  more » « less
Award ID(s):
1709972
PAR ID:
10094913
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
ACS nano
ISSN:
1936-0851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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