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Electron-phonon and magnetoelastic interactions in ferromagnetic Co[N(CN)2]2
T V Brinzari1, J T Haraldsen, P Chen
1Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA.
Physical Review Letters
|August 13, 2013
Summary
We uncovered charge-lattice-spin coupling in Cobalt bis(dicyanamide) using spectroscopy and calculations. This reveals how magnetic fields drive energy transfer through electron-phonon coupling and magnetoelastic effects.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spectroscopy
Background:
- Understanding charge-lattice-spin coupling is crucial for designing advanced materials.
- Cobalt bis(dicyanamide) (Co[N(CN)2]2) is a material exhibiting complex magnetic and electronic properties.
Purpose of the Study:
- To investigate the dynamic aspects of charge-lattice-spin coupling in Co[N(CN)2]2.
- To elucidate the interplay between electronic excitations, lattice vibrations, and magnetic fields.
Main Methods:
- Combined Raman and infrared vibrational spectroscopies.
- Lattice dynamics calculations.
- Magnetization measurements.
Main Results:
- Identified electron-phonon coupling driven by magnetic field-induced avoided crossing between Co2+ electronic excitation and ligand phonons.
- Observed a magnetoelastic effect indicating a flexible local CoN6 environment.
- Demonstrated the facile energy transfer across multiple scales in the system.
Conclusions:
- The study reveals dynamic charge-lattice-spin coupling mechanisms in Co[N(CN)2]2.
- Magnetic fields play a key role in modulating these interactions.
- The findings provide insights into energy transfer dynamics in correlated electron systems.
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