DISTRIBUTION OF MANGANESE IONS IN MAGNESIUM-ALUMINUM SPINELS OF DIFFERENT STOICHIOMETRIES

Citation
N. Mironova et al., DISTRIBUTION OF MANGANESE IONS IN MAGNESIUM-ALUMINUM SPINELS OF DIFFERENT STOICHIOMETRIES, Optical materials, 6(3), 1996, pp. 225-232
Citations number
20
Categorie Soggetti
Material Science",Optics
Journal title
ISSN journal
09253467
Volume
6
Issue
3
Year of publication
1996
Pages
225 - 232
Database
ISI
SICI code
0925-3467(1996)6:3<225:DOMIIM>2.0.ZU;2-Q
Abstract
Cathodoluminescence (CL), photoluminescence (PL) and EPR spectra of na tural and synthetic spinels have been measured. CL spectra reveal two emission bands caused by transitions within Mn2+ ion. Relative intensi ties of green and red emission of Mn2+ have been compared during simul taneous excitation of tetra- and octa-coordinated manganese ions under electron beam. Growth of relative intensity of Mn2+ CL in tetrahedral sites has been found in common with decrease of manganese relative co ncentration. A peculiar Mn-associated FL; which is typical for 3d(3) i ons, has been observed in lilac natural spinel. Proceeding from positi on of optical band, the corresponding coordination has been chosen. Si mulating EPR spectra have been used to estimate the degree and kind of disorder of nearest neighbours of Mn2+ ions.