LUMINESCENCE IN DIAMONDS OF THE SAO LUIZ PLACER (Brazil)
a:2:{s:4:"TEXT";s:220:"V.P. Mironov1, A.L. Rakevich1, F.A. Stepanov1, A.S. Emel’yanova1, D.A. Zedgenizov2, V.S. Shatsky2,3,4, H. Kagi5, E.F. Martynovich1,6";s:4:"TYPE";s:4:"html";}
1Irkutsk Division of the Institute of Laser Physics, Siberian Branch of the Russian Academy of Sciences, ul. Lermontova 130a, Irkutsk, 664033, Russia
2V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia
3A.P. Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, ul. Favorskogo 1a, Irkutsk, 664033, Russia
4Novosibirsk State University, ul. Pirogova 2, Novosibirsk, 630090, Russia
5Geochemical Research Center (GRC), Graduate School of Science, University of Tokyo, Tokyo, 113-0033, Japan
6Irkutsk State University, ul. Karla Marksa 1, Irkutsk, 664003, Russia
Keywords: Diamond, defect, luminescence, laser, spectrum, microscopy
Subsection: PETROLOGY, GEOCHEMISTRY, AND MINERALOGY
Abstract
Plates made of diamonds from the São Luiz province (Brazil) were investigated by confocal scanning luminescence microscopy. The samples have many macroinhomogeneities (cracks and inclusions), but there is a quasi-uniform distribution of luminescence centers in the bulk. At all investigated points of the crystals, the same group of centers was observed: N3, H4, 575, and a red band with a maximum at 690–700 nm. The visible nonuniformities in the distribution of luminescence over the area of the plates are determined by relatively small fluctuations in the ratio of the intensities of individual bands in the spectra. Nitrogen centers of different degrees of aggregation (H4, N3, and 575 nm, with four, three, and one nitrogen atom, respectively) coexist in these crystals. In the same zones of the samples, the distribution of blue luminescence (N3 centers) is diffuse (uniform), but the distribution of yellow-green luminescence is characterized by layering on (111). This might be a consequence of the tangential growth of octahedron faces or a result of plastic deformation of the crystals and dislocations along (111).
DOI: http://dx.doi.org/10.1016/j.rgg.2015.04.004
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