Hybrid quantum-classical simulations of magic angle spinning dynamic nuclear polarization in very large spin systems

File

2022-RossiniAaron-HybridQuantum.pdf (7.5 MB)

Date

2022-03-28

Authors

Perras, Frédéric A.
Carnahan, Scott L.
Lo, Wei-Shang
Yu, Jiaqi
Huang, Wenyu
Rossini, Aaron

Publisher

AIP Publishing

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Authors

Huang, Wenyu

Person

Rossini, Aaron

Person

Organizational Units

Chemistry

Organizational Unit

Ames Laboratory

Organizational Unit

Department

ChemistryAmes Laboratory

Abstract

Solid-state nuclear magnetic resonance can be enhanced using unpaired electron spins with a method known as dynamic nuclear polarization (DNP). Fundamentally, DNP involves ensembles of thousands of spins, a scale that is difficult to match computationally. This scale prevents us from gaining a complete understanding of the spin dynamics and applying simulations to design sample formulations. We recently developed an ab initio model capable of calculating DNP enhancements in systems of up to ∼1000 nuclei; however, this scale is insufficient to accurately simulate the dependence of DNP enhancements on radical concentration or magic angle spinning (MAS) frequency. We build on this work by using ab initio simulations to train a hybrid model that makes use of a rate matrix to treat nuclear spin diffusion. We show that this model can reproduce the MAS rate and concentration dependence of DNP enhancements and build-up time constants. We then apply it to predict the DNP enhancements in core–shell metal-organic-framework nanoparticles and reveal new insights into the composition of the particles’ shells.

Comments

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Perras, Frédéric A., Scott L. Carnahan, Wei-Shang Lo, Charles J. Ward, Jiaqi Yu, Wenyu Huang, and Aaron J. Rossini. "Hybrid quantum-classical simulations of magic angle spinning dynamic nuclear polarization in very large spin systems." The Journal of Chemical Physics 156, no. 12 (2022): 124112., and may be found at DOI: 10.1063/5.0086530. Copyright 2022 Author(s). Posted with permission.