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arXiv · 2404.12945

Modelling the magnetic properties of 1D arrays of FePc molecules

Roman Pico·Alejandro Rebola·Jorge Lasave·Paula Abufager·Ignacio Hamad
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Abstract

We investigate the magnetic properties of Fe Phthalocyanines (FePc) that are experimentally arranged in quasi one-dimensional chains when they are grown in thin films or powders. By means of DFT calculations we reproduce the structural parameters found in experiments, and then we build a generalized Heisenberg magnetic model with single ion anisotropy, and calculate its parameters. The results show a anisotropic exchange interaction $J$ between FePc molecules, and an easy plane single ion anisotropy $D$. By means of Monte Carlo simulations, with this model, we found an explanation to the non-saturation of the magnetization found at high fields, which we interpret is due to the anisotropic exchange interaction $J$. Finally, we also investigate the presence of magnetic solitons versus temperature and magnetic field. This results provide additional evidence that FePc is a soliton bearing molecular compound, with solitons easily excited mainly in the molecular $xy$ plane.

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Roman Pico, Alejandro Rebola, Jorge Lasave, Paula Abufager, Ignacio Hamad. 2024-04-19. Modelling the magnetic properties of 1D arrays of FePc molecules. https://doi.org/10.1021/acs.jpcc.4c00025

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