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Information × Registration Number 0224U002346, 0122U001833 , R & D reports Title Optically stimulated luminescence in new dosimetric materials based on doped borate glass and glassnanoceramic popup.stage_title Head Padliak Bohdan V., д.ф.-м.н. Registration Date 12-02-2024 Organization OG Vlokh Institute of Physical Optics of the Ministry of Education and Science of Ukraine popup.description2  High-quality glasses with the compositions Li2B4O7:Mn,Eu, Li2B4O7:Mn,Sm, Li2B4O7:Mn,Er, containing 1.0 mol.% of MnO2 and RE2O3 (RE – Eu, Sm, Er) impurities were obtained for the first time by the method of high-temperature melting, and their detailed studies were carried out using X-ray diffraction, electron paramagnetic resonance (EPR) and optical spectroscopy methods. Analysis of EPR and optical spectroscopy data showed that the Mn impurity is incorporated in the structural network of Li2B4O7:Mn,Eu, Li2B4O7:Mn,Sm, and Li2B4O7:Mn,Er glasses in the form of Mn2+ ions (3d5) and Mn3+ (3d4). Three types of Mn2+ centers were identified in the studied glasses: single Mn2+ centers (1) in strongly distorted sites (the ratio of rhombic and axial constants |E/D| ≤ 1/3), single Mn2+ centers (2) in sites with an almost cubic symmetry (D = 0, E = 0) and Mn2+ pair centers and their small clusters, coupled by magnetic dipolar and exchange interactions, respectively. The optical absorption spectra of Li2B4O7:Mn,Eu, Li2B4O7:Mn,Sm, and Li2B4O7:Mn,Er glasses contains a very broad intense band with maxima at 464 nm (in the Li2B4O7:Mn,Eu sample) and 467 nm (in the Li2B4O7:Mn,Sm and Li2B4O7:Mn,Er samples), which belong to the transition 5Eg(D) → 5T2g(D) of Mn3+ ions, and a series of characteristic narrow lines of the Eu3+ (4f6, 7F0), Sm3+ (4f5, 6H5/2), and Er3+ (4f11, 4I15/2) ions, respectively. The emission spectra of the Li2B4O7:Mn,Eu, Li2B4O7:Mn,Sm, and Li2B4O7:Mn,Er glasses have a broad band corresponding to the 4T1g(G) → 6A1g(S) transition of Mn2+ ions and narrow bands corresponding to the 5D0 → 7FJ (J = 0 – 4) transitions of Eu3+ ions in Li2B4O7:Mn,Eu glass and 3 characteristic bands in the yellow-orange-red range belonging to the 4G5/2 → 6H5/2, 6H7/2, 6H9/2 transitions of Sm3+ ions. The RE3+ → Mn2+, Mn3+ and Mn2+ → Mn3+ energy transfer processes were confirmed, which explains the absence of Er3+ luminescence in Li2B4O7:Mn,Er glass and Mn3+ in all glasses. Product Description popup.authors Adamiv Volodymyr T. Adamenko Dmytro I. Vasylkiv Yurii V. Mys Oksana H. Padlyak Bohdan V. Say Andrii S. Teslyuk Ihor M. popup.nrat_date 2024-02-12 Close