Intervalence charge transfer transition of Co2+-Ti4+ ion pair in α-Al2O3:Co,Ti crystal
| Autor: | Yongsheng Li, Shouguo Guo, Xiqi Feng, Yan Kang, Xiaozhen Han |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Materials science
Mechanical Engineering Metals and Alloys Analytical chemistry Corundum 02 engineering and technology Intervalence charge transfer engineering.material 010502 geochemistry & geophysics 021001 nanoscience & nanotechnology 01 natural sciences Ion Crystal Full width at half maximum Heteronuclear molecule Mechanics of Materials Absorption band Materials Chemistry engineering Absorption (chemistry) 0210 nano-technology 0105 earth and related environmental sciences |
| Zdroj: | Journal of Alloys and Compounds. 768:1058-1063 |
| ISSN: | 0925-8388 |
| DOI: | 10.1016/j.jallcom.2018.07.314 |
| Popis: | A new optical absorption band centered at 356 nm was observed in Co/Ti co-doped synthetic corundum in ultraviolet (UV) region while it doesn't exist in corundum single doped with cobalt or titanium. It is featured with high optical absorption intensity, full width at half maxima (FWHM, greater than 3000 cm−1), strong polarization along the metal ion-metal ion direction, which is consistent with the optical characteristics of intervalence charge transfer transition (IVCT). We propose that the 356 nm absorption band is generated by IVCT of Co2+-Ti4+ heteronuclear ion pair whose formation mechanism would be discussed briefly in this paper. Co2+-Ti4+ was found for the first time in corundum and is the second heteronuclear ion pair discovered in corundum in addition to the known Fe2+-Ti4+. |
| Databáze: | OpenAIRE |
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