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Updated: Jun 3, 2026
06:53
Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Ferromagnetic interactions in hosted bipartite materials--generalized-double-exchange and generalized-superexchange
Antonis N Andriotis1, Sergey Lisenkov, Madhu Menon
1Institute of Electronic Structure and Laser, FORTH, PO Box 1527, 71110 Heraklio, Crete, Greece. andriot@iesl.forth.gr
Summary
Defect-induced magnetism in dilute magnetic semiconductors is explained by a molecular generalization of double-exchange interactions. This mechanism, driven by codopant complementarity, facilitates magnetic coupling in materials like ZnO and GaN.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid-State Chemistry
Background:
- Defect-induced magnetism in dilute magnetic semiconductors challenges existing theories.
- Conventional superexchange and double-exchange interactions fail to explain long-range magnetic order below the percolation threshold.
- Codoping-induced magnetism offers potential explanations but lacks a clear theoretical framework.
Purpose of the Study:
- To propose a novel theoretical framework for understanding defect-induced magnetism in codoped non-magnetic materials.
- To generalize atomic double-exchange and superexchange interactions to a molecular level for bipartite lattices.
- To investigate the role of defect complementarity in facilitating magnetic interactions.
Main Methods:
- Theoretical calculations using ab initio methods.
- Application of a molecular generalization of atomic double-exchange and superexchange interactions.
- Analysis of codoped ZnO and GaN with transition metal impurities in various configurations.
Main Results:
- Defect-induced magnetism can be explained by molecular interactions within hosted bipartite codopant structures.
- Codopant complementarity is identified as a crucial factor for developing magnetism.
- Magnetic coupling occurs among spin-polarized molecular units, facilitated by the codopant structures.
Conclusions:
- The proposed molecular generalization provides a unified mechanism for defect-induced magnetism.
- The findings are supported by previous studies on C(60)-based polymers, indicating universality.
- This work offers new insights into the design and understanding of magnetic semiconductor materials.
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