Ligand field bands of Mn/2+/ and Fe/3+/ luminescence centres and their site occupancy in plagioclase feldspars
Abstract
An investigation is conducted of the infrared emitting Fe(3+) centers and of the isoelectronic Mn(++) centers which give rise to the green emission band, using optical excitation spectroscopy. This technique makes it possible to observe clearly ligand-field bands of these ions, which are usually present as impurities in the plagioclase. No special sample preparation is required and measurements can be made using microcrystalline powders. The equipment used consisted of a double chopper arrangement attached to a scanning reflection grating monochromator with a 400 W xenon high pressure arc source. Attention is given to the spectra of Mn(++) centers, the site occupancy of the Mn(++) centers, the spectra of Fe(++) centers, and the site occupancy of Fe(3+).
- Publication:
-
Modern Geology
- Pub Date:
- 1978
- Bibcode:
- 1978ModGe...6..199T
- Keywords:
-
- Feldspars;
- Iron;
- Ligands;
- Luminescence;
- Manganese;
- Metal Ions;
- Cations;
- Emission Spectra;
- Impurities;
- Infrared Spectra