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Mn3+ in trigonal bipyramidal coordination: a new blue chromophore
Andrew E Smith1, Hiroshi Mizoguchi, Kris Delaney
1Department of Chemistry, Oregon State University, Corvallis, Oregon 97330-4003, USA.
Journal of the American Chemical Society
|November 11, 2009
Summary
Trivalent manganese (Mn3+) creates a vivid blue color in oxides. This occurs due to specific electronic transitions in its trigonal bipyramidal coordination, causing light absorption.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Solid-State Physics
Background:
- The color of oxides is often determined by the electronic structure of transition metal ions.
- Understanding the origin of color in oxides can lead to novel material design.
Purpose of the Study:
- To investigate the origin of the intense blue color imparted by trivalent manganese (Mn3+) in oxides.
- To elucidate the electronic and optical properties responsible for this phenomenon.
Main Methods:
- Optical measurements were performed to analyze the absorption spectra.
- First-principles density functional theory (DFT) calculations were used to model the electronic structure.
Main Results:
- Trivalent manganese (Mn3+) in trigonal bipyramidal coordination causes intense blue coloration in oxides.
- The blue color arises from strong absorption in the red/green region of the spectrum.
- This absorption is attributed to a symmetry-allowed optical transition involving Mn 3d states hybridized with O 2p states.
Conclusions:
- The observed blue color is a general feature of diluted Mn3+ in this specific coordination environment.
- The findings provide a fundamental understanding of color centers in oxides and potential for tuning optical properties.
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