Transition Metal Ions in Crystals with the Fluorite Structure

Ab initio model potential embedded cluster calculations including lattice relaxation and polarization: Local distortions on Mn2+-doped CaF2

“…34,35 Consequently, the AIMP/SM calculations performed in this paper correspond to an embedded MnF 8 6Ϫ cluster, which is the simplest cluster in which the Mn-F interactions can be taken into account in a fully ab initio approach.…”

EPR spectra of the Mn2+ion in the oxyfluoride glass ceramics containing BaF2nanocrystalline phase

“…The Mn 2+ ion are particularly useful for investigation of the disordered media like glasses and powders since it has practically isotropic hyperfine (HF) interaction constant [6,7,8]. Coordination of neighboring fluorine nuclei exhibits additional superhyperfine (SHF) interaction which renders the nearest environment of the paramagnetic probe in the EPR spectra as additional SHF structure [9]. Although, information of SHF interaction in disordered media remains obscured due to large distribution of EPR parameter values, if the SHF interaction is by large extent isotropic it is possible to observe spectral features characteristic to certain crystalline structures.…”

Ab initio model potential study of the optical absorption spectrum of Mn2+-doped CaF2

“…[1][2][3][4][5][6] It is well-known that d n impurities can notably alter the properties of the host crystals in different ways. Noteworthy, and most related to the interests of this work, they can give origin to local absorption/emission bands within the spectral region where the host is transparent, this being of fundamental and practical interest.…”

“…Noteworthy, and most related to the interests of this work, they can give origin to local absorption/emission bands within the spectral region where the host is transparent, this being of fundamental and practical interest. [1][2][3][4][5][6] They can also alter the efficiency for production of color centers in halide crystals after ionizing irradiation. 1,7,8 They can sensitize or be sensitized along energy transfer processes involving codoped rare earth impurities, this augmenting further their importance in the search for new phosphors and laser systems.…”

“…[9][10][11] Numerous examples of these impurity induced changes and their technological applications can be found in the literature devoted to the research of potential solid state lasers, radiation damage, etc. [1][2][3][4][5][6][7][8][9][10][11] Notably, most of the effort has been concentrated on the study of 3d impurities in six-and fourfold coordination as well as on impurities showing local spinallowed absorption/emission bands. Mn 2ϩ -doped fluorite is an exception to this.…”