Year: 2025
Type: article
Abstract: In nuclear magnetic resonance (NMR), the bulk magnetization of a sample is commonly assumed to be proportional to spin polarization, with each spin of the same type contributing equally to the measured signal. Herein, the high‐field theorem for general spin‐I systems (where I is the spin quantum number): the total measurable NMR signal remains unaffected by the grouping of spins into equivalent units (e.g., molecules) is proved, provided the system is at thermodynamic equilibrium in the high field limit (, where is the Larmor frequency and characterizes internal spin–spin interactions). The results are derived using both magnetization equations and density matrix formalism. The theorem, however, does not extend to conditions far from thermodynamic equilibrium (e.g., hyperpolarization), NMR of solids in the regime when quadrupolar or dipole–dipole interactions are not negligible, and zero‐ to ultralow‐field NMR. Three educational problems designed to deepen understanding of the material in classroom settings are also presented. This work reinforces established principles in magnetic resonance but also highlights areas for further exploration.
Source: ChemPhysChem
Authors: Danila A. Barskiy, Andrey N. Pravdivtsev
Language: English
Subfield: Spectroscopy
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,550
Awards: G1580916385, G165400314, G234614750, G2819565804, Parawasserstoffinduzierte Hyperpolarisation von 13Cmarkierten Ketocarbonsäuren für medizinische Anwendungen: Synthese, Polarisationsübertragung, 13CMRT, TRY-IBD - Multi-dimensionale Auflösung des Tryptophan-abhängigen Immunmetabolismus als neues pathophysiologisches Prinzip bei chronisch entzündlichen Darmerkrankungen - MRT-Tryptophanmarker in-vitro und in-vivo, Unabhängiger parawasserstoffinduzierter zweiphasenHyperpolarisator für Ultraniederfeld und Ultrahochfeld MR (2PPHIP), G791659679
OpenAlex ID: W4409712754