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Updated: Mar 22, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Momentum-dependent band spin splitting in semiconducting MnO2: a density functional calculation
Yusuke Noda1, Kaoru Ohno2, Shinichiro Nakamura3
1RIKEN Innovation Center, Nakamura Laboratory, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. yusuke.noda@riken.jp and Department of Physics, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan.
Physical Chemistry Chemical Physics : PCCP
|April 28, 2016
Summary
Manganese dioxide (MnO2) crystal phases exhibit unique electronic states crucial for water-splitting. Spin-dependent electronic properties are linked to crystal structure and magnetic interactions, offering insights for photocatalyst design.
Area of Science:
- Materials Science
- Solid State Physics
- Computational Chemistry
Background:
- Manganese oxide compounds are promising for photochemical water-splitting.
- Understanding the electronic states of manganese dioxide (MnO2) is key to optimizing its photocatalytic activity.
Purpose of the Study:
- Investigate the electronic states of pristine MnO2 in various crystal phases.
- Elucidate the relationship between crystal structure, magnetic order, and electronic properties.
Main Methods:
- Employed spin-polarized density functional theory (DFT) with Hubbard U correction.
- Analyzed geometrical structures and band dispersions of α-, β-, δ-, and λ-MnO2 crystals.
- Examined ferromagnetic (FM) and antiferromagnetic (AFM) collinear magnetic orders.
Main Results:
- Identified superexchange interactions via Mn-O-Mn groups as the origin of magnetic interactions.
- Observed momentum-dependent band spin splitting in AFM α-, β-, and δ-MnO2, but not in AFM λ-MnO2.
- Linked spin-split band dispersions to the orientations of Mn-centered oxygen octahedra.
Conclusions:
- Established a connection between spin-dependent electronic states and the crystallography of manganese oxides.
- Provided a theoretical basis for understanding experimental observations in MnO2 photocatalysis.
- Highlighted the importance of crystal phase and magnetic ordering for MnO2 electronic properties.
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