ModelFreeFFC

ModelFreeFFC is a freeware standalone Matlab® tool, developed at the University of Bologna (Bologna, Italy), with a graphical interface (GUI) for Windows, Linux OSs useful for fitting nuclear magnetic relaxation dispersion (NMRD) curves obtained by fast field cycling nuclear magnetic resonance (FFC-NMR) relaxometry measurements. The model used to fit the NMRD curve is supposed to be the “model free” one [1].
The Software is provided 'AS IS', without warranty of any kind, express or implied. In no event shall the copyright holder(s) be liable for any claim, data loss, loss of profits, damages or other liability arising from the Software's use or misuse. You use it at your own risk. Please read the License document for the terms of use (“License_ModelFree.pdf”).
In addition to the compiled standalone GUI version (developed with the App Designer Matlab tool), there is also a standalone command- line executable version, both for Windows OS and Linux OS (See SOFTWARE INSTALLATION paragraph). The tool allows the user to handle some parameters that greatly influence the quality of the NMR maps and the computation time to perform the inversion. There is also a set of diagnostic tools that allow the user to evaluate the quality of the measured data. Remember that to have a good inversion, it is fundamental to have high-quality data (data without too many outliers or electronic baseline, relaxation curves not correctly sampled or distorted, etc.).

Reference
[1] P. Lo Meo, S. Terranova, A. Di Vincenzo, D. Chillura Martino and P. Conte. Heuristic Algorithm for the Analysis of Fast Field Cycling (FFC) NMR Dispersion Curves. Anal. Chem. 2021,  93, 24, 8553–8558. https://doi.org/10.1021/acs.analchem.1c01264.