DOI: 10.5061/dryad.wm37pvn00
title: Mapping structures and dynamics with frequency-correlated diffusion exchange

description: Understanding molecular motion in diffusion-driven complex environments is
 critical for designing sustainable materials and improving chemical
 processes. Here, we introduce a multidimensional nuclear magnetic
 resonance (NMR) method that captures how molecular populations exchange
 across different dynamic regimes. By extending the modulated gradient
 spin-echo (MGSE) technique to include frequency–frequency correlations,
 our approach reveals diffusion pathways that are otherwise obscured in
 heterogeneous systems. Implemented on a unilateral NMR magnet, the method
 eliminates gradient pulsing constraints and accesses dynamics in the
 kilohertz regime. We apply this technique to swelling and acid-catalyzed
 deconstruction of crosslinked and linear polymers to observe how
 structural heterogeneity evolves over time. By linking molecular motion to
 topology and chemical state, we extract physical metrics such as fractal
 surface dimensionality and reaction wavefront velocity–properties
 inaccessible with standard diffusion measurements. This work expands the
 capabilities of NMR for probing soft matter, with implications for polymer
 recycling and materials design.
description: # Mapping structures and dynamics with frequency-correlated diffusion
 exchange Dataset DOI: [10.5061/dryad.wm37pvn00](10.5061/dryad.wm37pvn00)
 ## Description of the data and file structure Raw multidimensional NMR
 MGSE-MGSE data output from Prospa v3.62 corresponding to the descriptions
 in the paper "Mapping structures and dynamics with
 frequency-correlated diffusion exchange." Zipped folder names
 indicate sample identity (listed below). Each sample folder contains 20
 subfolders named N150, N1000, N1150, N1200, N1250, ... N11000. These
 folders are numbered to indicate the number of echoes recorded within the
 first 55-ms MGSE block; the number string following "N1" is the
 number of echoes incremented in that block. This can be converted to the
 modulation frequency of the indirect dimension of the MGSE correlation.
 Each of these folders contains subfolders named by number of echoes
 recorded within the second (readout dimension) MGSE block, also 55-ms
 here. The number of echoes in the readout train was also incremented from
 50 to 1000 in steps of 50; this can be converted to the modulation
 frequency of the direct dimension of the MGSE correlation. The time and
 intensity (real part) data are stored in the first and second columns of
 the csv files named "data.csv" in each sub-subfolder. These
 files are all that is needed to load the data and can be opened in many
 softwares (Excel, Python, Matlab, etc, as well as any other text editor);
 the 'acqu.par' files can be opened in any text editor;
 additional files with extensions .1D, .2D, .PT1, and .PT2 can be used to
 open 1D and 2D data or plots, respectively, directly in Prospa, but are
 redundant (these were included for completeness in data reporting;
 however, it is unnecessary for viewers to use these files because all
 relevant parameters are reported directly in the manuscript, SI, and
 readme here on Dryad; and the raw data is included in the
 'data.csv' files). Experiments were collected on a 0.3 T
 NMR-MOUSE unilateral magnet with a constant magnetic field gradient of 7
 T/m. Analysis codes are included in the Supplemental Materials of the
 paper to process the data in MatLab; alternatively, data can be readily
 analyzed in any software that will load csv or ascii files. ### Files and
 variables #### File: PDK-ppg2000-monoglyme-swelled-5ms.zip
 **Description:** raw multidimensional MGSE experimental data for linear
 PDK-PPG-2000 swelled in monoglyme with experimental mixing time of 5 ms.
 #### File: PDK-ppg2000-HCl-endpoint-5ms.zip **Description:** raw
 multidimensional MGSE experimental data for linear PDK-PPG-2000 after 5.0
 M HCl depolymerization reaction endpoint with experimental mixing time of
 5 ms. #### File: PDK-T5000-HCl-rxn-5ms.zip **Description:**  raw
 multidimensional MGSE experimental data for crosslinked PDK-T5000 during
 5.0 M HCl depolymerization reaction with experimental mixing time of 5 ms.
 #### File: PDK-ppg2000-monoglyme-HCl-endpoint-5ms.zip **Description:** raw
 multidimensional MGSE experimental data for linear PDK-PPG-2000 after 5.0
 M HCl depolymerization reaction endpoint (pre-swelled with monoglyme) with
 experimental mixing time of 5 ms. #### File:
 PDK-ppg2000-monoglyme-HCl-rxn-5ms.zip **Description:**  raw
 multidimensional MGSE experimental data for linear PDK-PPG-2000 during 5.0
 M HCl depolymerization reaction (pre-swelled with monoglyme) with
 experimental mixing time of 5 ms. #### File:
 PDK-T5000-monoglyme-HCl-endpoint-5ms.zip **Description:** raw
 multidimensional MGSE experimental data for crosslinked PDK-T5000 after
 5.0 M HCl depolymerization reaction endpoint (pre-swelled with monoglyme)
 with experimental mixing time of 5 ms. #### File:
 PDK-ppg2000-HCl-rxn-5ms.zip **Description:** raw multidimensional MGSE
 experimental data for linear PDK-PPG-2000 during 5.0 M HCl
 depolymerization reaction with experimental mixing time of 5 ms. ####
 File: PDK-T5000-HCl-endpoint-5ms.zip **Description:** raw multidimensional
 MGSE experimental data for crosslinked PDK-T5000 after 5.0 M HCl
 depolymerization reaction endpoint with experimental mixing time of 5 ms.
 #### File: PDK-T5000-monoglyme-HCl-rxn-5ms.zip **Description:** raw
 multidimensional MGSE experimental data for crosslinked PDK-T5000 during
 5.0 M HCl depolymerization reaction (pre-swelled with monoglyme) with
 experimental mixing time of 5 ms. #### File:
 PDK-T5000-monoglyme-swelled-5ms.zip **Description:** raw multidimensional
 MGSE experimental data for crosslinked PDK-T5000 swelled with monoglyme
 with experimental mixing time of 5 ms.