About relACs

A relACs program was created by Mikolaj Żychowicz (member of MLMG) and Wiktor Żychowicz in 2021. This software offers a convenient route to analyze the full set of alternate-current (ac) magnetic data for molecular nanomagnets using various models for ac magnetic characteristics and the further reliable determination of diverse magnetic relaxation processes. 

In particular, the relACs program enables the precise determination of magnetic relaxation times from the simultaneous fitting of ac magnetic characteristics (frequency dependences of out-of-phase and in-phase magnetic susceptibilities together with the related Argand plots) using models for complex-valued ac susceptibility at the indicated conditions of dc magnetic field and temperature as well as the further determination of final parameters of operating relaxation processes from the simultaneous 3D fitting of temperature- and field-dependences of relaxation times. 

The relACs program was developed in Python and uses the following commonly accessible libraries: 

(a) PyQT5 used as a UI library,

(b) Matplotlib as a plotting library, 

(c) Numpy, enabling efficient processing of array-like data in Python,  

(d) Pandas helping in the data analysis part of the program, 

(e) Scipy as a source of used numerical algorithms, 

(f) Numba as a JIT (Just in Time) compiler used to accelerate frequently called Python functions to bring their execution time closer to native and compiled languages levels. 

The program operates on the raw data from ac magnetic measurements on a Quantum Design MPMS-3 Evercool magnetometer; however, it can also operate on the data from other MPMS devices. All calculations can be performed using the Windows system; however, this program can easily work on all main desktop platforms. 

The relACs program is free-of-charge and can be downloaded from this page. For technical queries regarding this program, please contact its authors through the contact details given in the software package, or directly email Mikolaj Żychowicz (mikolaj.zychowicz@uj.edu.pl). The source code can be found here.

We kindly request that any results obtained through the use of relACs software are accompanied by the following reference: M. Liberka, M. Zychowicz, W. Zychowicz, S. Chorazy, Chem. Commun., 2022, 58, 6381. DOI: 10.1039/D2CC02238A

Manual for the previous version of the software can be found on following link (p. S44). 


2021 Multifunctional Luminescent Materials Group
Faculty of Chemistry | Jagiellonian University