Simulation and analysis of 13C spin-rotation nuclear magnetic resonance relaxation rates of methyl groups

• Published in: Journal of molecular liquids Vol. 399; p. 124391
• Main Authors: Hernández-Tanguma, Alejandro, Ariza-Castolo, Armando
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-04-2024
• Subjects: Internal rotor dynamics; Methyl rotation; Molecular dynamics; NMR relaxation; Nuclear spin-rotation coupling; DD; BRS; PAS; Mα; τJ; Iα; Molecular dynamics; IR; I; NSR; M; NMR relaxation; Internal rotor dynamics; Nuclear spin-rotation coupling; Methyl rotation; R1
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2024.124391

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•Nuclear spin-rotation differentiates 13C nuclear spin relaxation in methyl groups.•Methyl group 13C nuclear spin-rotation is estimated in the bond reference frame.•Force-field molecular dynamics trajectories reproduce the angular correlation times.
This work analyzes the nuclear spin–rotation contribution to the nuclear magnetic resonance relaxation of methyl groups from 10 rigid compounds (eight benzene derivatives with one, two, or three methyl groups and two bicyclic molecules) with internal rotation axes not aligned to the smallest molecular moment of inertia via molecular dynamics simulation and ab initio calculation. The molecular dynamics simulation and ab initio calculation of nuclear spin-rotation coupling constants reproduce the experimental behavior in selected systems. The presented methodology can help in the analysis and interpretation of experimental relaxation data.