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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Spin-Phonon Coupling and Slow-Magnetic Relaxation in Pristine Ferrocenium.
Martín Amoza1, Lindley Maxwell1,2, Núria Aliaga-Alcalde3,4
1Departament de Química Inorgànica i Orgànica and, Institut de Recerca de Química Teòrica i Computacional, Universitat de Barcelona, Diagonal 645, 08028, Barcelona, Spain.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 28, 2021
Summary
Ferrocenium exhibits field-induced single-molecule magnet behavior, unlike cobaltocene. Quantum mechanical calculations and spin relaxation analysis reveal key mechanisms, with a specific vibrational mode dominating low-temperature spin dynamics.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Quantum Mechanics
Background:
- Ferrocenium complexes are investigated for their magnetic properties.
- Understanding spin dynamics is crucial for developing molecular magnets.
- Cobaltocene serves as a comparative system for spin relaxation studies.
Purpose of the Study:
- To elucidate the spin dynamic properties of non-substituted ferrocenium.
- To investigate the field-induced single-molecule magnet behavior of ferrocenium.
- To analyze the mechanisms governing spin relaxation in ferrocenium.
Main Methods:
- Experimental measurements of spin dynamics in DMF solution and powder.
- Multireference quantum mechanical calculations for electronic structure.
- Analysis of spin relaxation pathways including quantum tunneling, Raman, direct, and local-mode mechanisms.
Main Results:
- Ferrocenium displays field-induced single-molecule magnet behavior.
- Cobaltocene lacks slow spin relaxation under tested conditions.
- Quantum calculations reveal non-Aufbau orbital occupation and significant magnetic anisotropy in ferrocenium.
- Spin relaxation is influenced by temperature, external field, and multiple mechanisms.
Conclusions:
- A specific low-energy vibrational mode is identified as the primary driver of spin relaxation at low temperatures.
- The vibrational energy of this mode aligns well with experimental findings.
- The study provides insights into the fundamental spin dynamics of ferrocenium complexes.
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