%0 Journal Article %T EPR and Optical Spectroscopy of Impurities in Two Synthetic Beryls %+ Institut des Sciences de la Terre d'Orléans (ISTO) %A Gaite, Jean-Michel %A Izotov, V. %A Nikitins, S. %A Prosvirnin, S.Y. %< avec comité de lecture %@ 0937-9347 %J Applied Magnetic Resonance %I Springer Verlag %V 20 %P 307-315 %8 2001 %D 2001 %R 10.1007/BF03162283 %Z Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]Journal articles %X Two synthetic beryls (Al2Be3Si6O18) of different color (purple and blue-green) were studied with electron paramagnetic resonance (EPR) and optical spectroscopy. In both crystals, the known spectra of Cu2+ and Fe3+ were observed with the same relative intensity. In the purple sample heated at 700°C in hydrogen atmosphere, two different kinds of Mn2+ EPR spectra were observed. The main one is pseudoaxial, it arises from ions substituted for Al3+ at position 4c of the structure. The weaker one is more complex, it has orthorhombic symmetry and is characterized by an unusually large zero-field splitting (B20 = 741·10-4 cm-1) and an isotropic hyperfine constant A = 70 G. This spectrum arises from Mn2+ at position 6f in the structure, normally occupied by Be. From optics, the blue-green color arises from Cu2+, while the purple one is due to Mn3+. %G English %L hal-00089733 %U https://insu.hal.science/hal-00089733 %~ INSU %~ CNRS %~ UNIV-ORLEANS %~ ISTO %~ OSUC