The spin-phonon relaxation mechanism of single-molecule magnets in the presence of strong exchange coupling

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Mondal, Sourav, Netz, Julia, Hunger, David, Suhr, Simon, Sarkar, Biprajit, van Slageren, Joris, Köhn, Andreas, Lunghi, Alessandro
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929616962191360
author Mondal, Sourav
Netz, Julia
Hunger, David
Suhr, Simon
Sarkar, Biprajit
van Slageren, Joris
Köhn, Andreas
Lunghi, Alessandro
author_facet Mondal, Sourav
Netz, Julia
Hunger, David
Suhr, Simon
Sarkar, Biprajit
van Slageren, Joris
Köhn, Andreas
Lunghi, Alessandro
contents Magnetic relaxation in coordination compounds is largely dominated by the interaction of the spin with phonons. Large zero-field splitting and exchange coupling values have been empirically found to strongly suppress spin relaxation and have been used as the main guideline for designing new molecular compounds. Although a comprehensive understanding of spin-phonon relaxation has been achieved for mononuclear complexes, only a qualitative picture is available for polynuclear compounds. Here we fill this critical knowledge gap by providing a full first-principle description of spin-phonon relaxation in an air-stable Co(II) dimer with both large single-ion anisotropy and exchange coupling. Simulations reproduce the experimental relaxation data with excellent accuracy and provide a microscopic understanding of Orbach and Raman relaxation pathways and their dependency on exchange coupling, zero-field splitting, and molecular vibrations. Theory and numerical simulations show that increasing cluster nuclearity to just four cobalt units would lead to a complete suppression of Raman relaxation. These results hold a general validity for single-molecule magnets, providing a deeper understanding of their relaxation and revised strategies for their improvement.
format Preprint
id arxiv_https___arxiv_org_abs_2412_04362
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle The spin-phonon relaxation mechanism of single-molecule magnets in the presence of strong exchange coupling
Mondal, Sourav
Netz, Julia
Hunger, David
Suhr, Simon
Sarkar, Biprajit
van Slageren, Joris
Köhn, Andreas
Lunghi, Alessandro
Materials Science
Magnetic relaxation in coordination compounds is largely dominated by the interaction of the spin with phonons. Large zero-field splitting and exchange coupling values have been empirically found to strongly suppress spin relaxation and have been used as the main guideline for designing new molecular compounds. Although a comprehensive understanding of spin-phonon relaxation has been achieved for mononuclear complexes, only a qualitative picture is available for polynuclear compounds. Here we fill this critical knowledge gap by providing a full first-principle description of spin-phonon relaxation in an air-stable Co(II) dimer with both large single-ion anisotropy and exchange coupling. Simulations reproduce the experimental relaxation data with excellent accuracy and provide a microscopic understanding of Orbach and Raman relaxation pathways and their dependency on exchange coupling, zero-field splitting, and molecular vibrations. Theory and numerical simulations show that increasing cluster nuclearity to just four cobalt units would lead to a complete suppression of Raman relaxation. These results hold a general validity for single-molecule magnets, providing a deeper understanding of their relaxation and revised strategies for their improvement.
title The spin-phonon relaxation mechanism of single-molecule magnets in the presence of strong exchange coupling
topic Materials Science
url https://arxiv.org/abs/2412.04362