Premium
Polarized luminescence and EPR study of Sn + centres in KCl:SnCl 2 crystals
Author(s) -
Egemberdiev Zh.,
Seeman V.,
Zazubovich S.,
Jaanson N.
Publication year - 1979
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.2220920139
Subject(s) - luminescence , electron paramagnetic resonance , excited state , absorption (acoustics) , crystal (programming language) , ion , absorption spectroscopy , chemistry , excitation , atomic physics , ground state , crystallography , materials science , nuclear magnetic resonance , physics , optics , optoelectronics , organic chemistry , quantum mechanics , computer science , composite material , programming language
Three types of Sn + centres, recently found by Delbecq et al. in KCl:SnCl 2 crystals irradiated at 77 K and warmed up to certain temperatures, are investigated by absorption, EPR, and polarized luminescence methods at 25 to 450 K. The intra‐centre luminescence peaks at 2.03, 2.06, and 2.02 eV are observed for all types of Sn + centres under excitation in the most intensive absorption bands of Sn + in the region from 6.4 to 5.6 eV and also in weak absorption bands at 5.1 to 3.1 eV. The connection of the observed absorption and emission bands with the Sn + centres of a certain structure is established by comparing the thermal stabilities of the Sn + centres obtained by the EPR and optical methods. The emission of all three types of Sn + centres is polarized along the C 4 crystal axis, which is probably caused by the orientation of the SnCl 2 −molecular ion in the crystal. The spectral bands of Sn + centres are connected with the electronic transitions between the fully occupied ground state and two groups of excited states of the SnCl 2 −molecular ion whose energies depend on the location of v c −with respect to SnCl 2 − . The connection of the geometrical structure of Sn + v c −centres with that of Sn 2+ v c centres in KCl:SnCl 2 crystals is discussed.