Coherent polarization transfer in chemically exchanging systems. Issue 16 (15th April 2020)

• Record Type: Journal Article
• Authors: Pravdivtsev, Andrey N.; Hövener, Jan-Bernd
• Is Part Of: Physical chemistry chemical physics. Volume 22:Issue 16(2020)
• Page Start: 8963
• Page End: 8972
• Publication Date: 2020-04-15
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp06873b
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Simulation of the interplay of coherent polarization transfer and chemical exchange described by superoperators and Monte Carlo simulations alike. Abstract : Signal Amplification by Reversible Exchange (SABRE) uses para -enriched dihydrogen, p H2, to boost the NMR signal by several orders of magnitude. Although the method was discovered more than a decade ago, the quest to optimize SABRE and to establish a complete description in silico is ever ongoing. The simulation of SABRE is exacerbated by a complex interplay of chemical exchange and coherent polarization transfer. Here, we compare two different simulation approaches, Markov chain Monte Carlo (MC) simulations and a modification of the Liouville von Neumann equation with superoperators of chemical exchange (SO). We apply these methods to simulate the fate of truncated and full, three and four spin-½ systems in two different experiments: continuous polarization at a constant or alternating B 0 field. For all cases, MC and SO provided similar results, and previously reported experimental data were well reproduced. It appears that both methods are well suited to approach this matter, while SO was faster than MC by several orders of magnitude in the cases discussed.