Theoretical investigations on the defect structures and spin Hamiltonian parameters for various orthorhombic Rh2+ centres in KTiOPO4 and KTiOAsO4

2015 ◽  
Vol 479 ◽  
pp. 21-25 ◽  
Author(s):  
Chang-Chun Ding ◽  
Shao-Yi Wu ◽  
Li-Juan Zhang ◽  
Guo-Liang Li ◽  
Zhi-Hong Zhang
Keyword(s):  
Defect Structures ◽  
Spin Hamiltonian ◽  
Theoretical Investigations ◽  
Hamiltonian Parameters

Theoretical Investigations Of The Spin Hamiltonian Parameters Of Zrsio4:Np4+

2004 ◽  
Vol 59 (7-8) ◽  
pp. 471-475
Author(s):  
Shao-Yi Wu ◽  
Hui-Ning Dong
Keyword(s):  
Experimental Data ◽  
Energy Levels ◽  
Structural Data ◽  
Superposition Model ◽  
Spin Hamiltonian ◽  
Theoretical Investigations ◽  
Structure Constants ◽  
Crystal Field Parameters ◽  
Hamiltonian Parameters ◽  
Theoretical Results

In this work, the spin Hamiltonian (SH) parameters g|| and g⊥, and the hyperfine structure constants A|| and A⊥ for ZrSiO4:Np4+ are investigated on the basis of the perturbation formulas of these parameters for a 5f3 ion in tetragonal (D2d) symmetry. In these formulas, the contributions to the SH parameters from the second-order perturbation terms, the admixtures of various energy levels and the covalency effect are taken into account. The related crystal-field parameters are calculated from the superposition model and the local structural data of the Zr4+ site occupied by the impurity Np4+. The calculated SH parameters agree reasonably with the experimental data. The validity of the theoretical results is discussed.

Theoretical Investigations of the Defect Structure for Ni3+ in ZnO

2011 ◽  
Vol 318 ◽  
pp. 41-45
Author(s):  
Zhi Hong Zhang ◽  
Shao Yi Wu ◽  
Shan Xiang Zhang
Keyword(s):  
Defect Structure ◽  
Impurity Center ◽  
Spin Hamiltonian ◽  
Theoretical Investigations ◽  
Ligand Orbital ◽  
High Valence State ◽  
Zno Crystal ◽  
Hamiltonian Parameters ◽  
Good Agreement ◽  
The Ideal

The defect structure for Ni3+ in ZnO crystal is theoretically investigated using the perturbation formulas of the spin Hamiltonian parameters for a 3d7 ion in trigonally distorted tetrahedra. In view of the significant covalency of the system due to the high valence state of Ni3+, the ligand orbital and spin-orbit coupling contributions are taken into account in a uniform way based on the cluster approach. The impurity Ni3+ is found not to occupy the ideal Zn2+ site in ZnO but to undergo the small axial displacement of about 0.044 Ǻ away from the oxygen triangle along the C3 axis. The theoretical spin Hamiltonian parameters based on the above impurity displacement show good agreement with the experimental data. The defect structure of this impurity center is compared with that for the similar Fe3+ in ZnO.

Studies of the spin Hamiltonian parameters and defect structures for Ag2+ in NaF and CsCdF3 crystals

2016 ◽  
Vol 484 ◽  
pp. 36-41 ◽  
Author(s):  
Li-Juan Zhang ◽  
Shao-Yi Wu ◽  
Chang-Chun Ding ◽  
Xian-Fen Hu ◽  
Jia-Jun He
Keyword(s):  
Defect Structures ◽  
Spin Hamiltonian ◽  
Hamiltonian Parameters

Theoretical studies of the defect structures and the spin Hamiltonian parameters for the Pd+ and Pd3+ centers in NH4Cl

2013 ◽  
Vol 1022 ◽  
pp. 45-49 ◽  
Author(s):  
Min-Quan Kuang ◽  
Shao-Yi Wu ◽  
Xian-Fen Hu ◽  
Zhi-Hong Zhang ◽  
Hua-Ming Zhang ◽  
...  
Keyword(s):  
Theoretical Studies ◽  
Defect Structures ◽  
Spin Hamiltonian ◽  
Hamiltonian Parameters

Theoretical Investigations for the Defect Structure and the Spin Hamiltonian Parameters of Divalent Cobalt in LiMgPO4

2021 ◽  
Vol 1032 ◽  
pp. 108-113
Author(s):  
Xu Sheng Liu ◽  
Shao Yi Wu ◽  
Yi Mei Fan ◽  
Xing Yuan Yu
Keyword(s):  
Defect Structure ◽  
Spin Hamiltonian ◽  
Size Mismatch ◽  
Local Structures ◽  
Distorted Octahedral ◽  
Theoretical Investigations ◽  
Divalent Cobalt ◽  
Structure Constants ◽  
Relative Compression ◽  
Hamiltonian Parameters

The spin Hamiltonian parameters (SHPs, g factors and hyperfine structure constants) defect structure for LiMgPO4 doped with 0.1% Co2+ at 4.2 K are theoretically investigated from the perturbation formulas of the SHPs for a rhombically distorted octahedral 3d7 cluster. The impurity Co2+ on host Mg2+ site is found to suffer the larger axial relative compression ratio ρ (≈ 0.76%) and the planar angular variation Δφ (≈ 6.64°) related to the host oxygen octahedron due to size mismatch. The calculated SHPs based on the above defect structure show good agreement with the measured results. Present study can be helpful to the preparation and characterization for the local structures for transition-metal impurities in lithium-magnesium phosphate, which may is helpful to search for the phosphor materials with better dosimetric characteristics.

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