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Title: Nuclear induction line shape: Non-Markovian diffusion with boundaries
The dynamics of viscoelastic fluids are governed by a memory function, essential yet challenging to compute, especially when diffusion faces boundary restrictions. We propose a computational method that captures memory effects by analyzing the time-correlation function of the pressure tensor, a viscosity indicator, through the Stokes–Einstein equation’s analytic continuation into the Laplace domain. We integrate this equation with molecular dynamics simulations to derive necessary parameters. Our approach computes nuclear magnetic resonance (NMR) line shapes using a generalized diffusion coefficient, accounting for temperature and confinement geometry. This method directly links the memory function with thermal transport parameters, facilitating accurate NMR signal computation for non-Markovian fluids in confined geometries.  more » « less
Award ID(s):
2002313
PAR ID:
10481184
Author(s) / Creator(s):
;
Publisher / Repository:
American institute of physics (AIP)
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
160
Issue:
2
ISSN:
0021-9606
Page Range / eLocation ID:
1-11
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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