scholarly journals Effects of excited states for d3 ions on spin-Hamiltonian parameters of the ground state 4A2 in axial-symmetrical crystal field

2007 ◽  
Vol 56 (1) ◽  
pp. 507
Author(s):  
Wei Qun ◽  
Yang Zi-Yuan ◽  
Wang Can-Jun ◽  
Xu Qi-Ming
Keyword(s):  
Crystal Field ◽  
Excited States ◽  
Ground State ◽  
Spin Hamiltonian ◽  
Hamiltonian Parameters

scholarly journals Терагерцовая спектроскопия магнитоэлектрика HoAl-=SUB=-3-=/SUB=-(BO-=SUB=-3-=/SUB=-)-=SUB=-4-=/SUB=-

2022 ◽  
Vol 130 (1) ◽  
pp. 59
Author(s):  
А.М. Кузьменко ◽  
В.Ю. Иванов ◽  
А.Ю. Тихановский ◽  
А.Г. Пименов ◽  
А.М. Шуваев ◽  
...  
Keyword(s):  
Crystal Field ◽  
Excited States ◽  
Ground State ◽  
Theoretical Study ◽  
Low Frequency ◽  
Local Symmetry ◽  
Matrix Elements ◽  
The Matrix ◽  
Excitation Conditions ◽  
Ground Multiplet

Experimental and theoretical study of submillimeter (terahertz) spectroscopic and magnetic properties of the rare-earth aluminum borate HoAl3(BO3)4 were performed at temperatures 3–300 K. In the transmittance spectra a number of resonance lines were detected at frequencies 2–35 cm–1 for different radiation polarizations. These modes were identified as transitions between the lower levels of the ground multiplet of the Ho3+ ion split by the crystal field, including both transitions from the ground state to the excited ones and transitions between the excited states. The established excitation conditions of the observed modes and the simulation of the spectra made it possible to separate the magnetic and electric dipole transitions and to determine the energies of the corresponding states, their symmetry, and the matrix elements of the transitions. Low-frequency lines that do not fit into the established picture of the electron states of Ho3+ were also found; these lines, apparently, correspond to the ions with the distorted by defects local symmetry of the crystal field.

Theoretical Studies of the Spin Hamiltonian Parameters and Local Distortions for Cu2+ in Alkaline Earth Lead Zinc Phosphate Glasses

2016 ◽  
Vol 71 (8) ◽  
pp. 769-775 ◽  
Author(s):  
Bo-Kun Wang ◽  
Shao-Yi Wu ◽  
Zi-Yi Yuan ◽  
Zi-Xuan Liu ◽  
Shi-Xin Jiang ◽  
...  
Keyword(s):  
Field Strength ◽  
Crystal Field ◽  
Alkaline Earth ◽  
Zinc Phosphate ◽  
Phosphate Glasses ◽  
Spin Hamiltonian ◽  
Local Structures ◽  
Crystal Field Strength ◽  
Lead Zinc ◽  
Hamiltonian Parameters

AbstractThe spin Hamiltonian parameters and local structures are theoretically studied for Cu2+-doped alkaline earth lead zinc phosphate (RPPZ, R=Mg, Ca, Sr, and Ba) glasses based on the high-order perturbation calculations for a tetragonally elongated octahedral 3d9 cluster. The relative elongation ratios are found to be ρ≈3.2%, 4.4%, 4.6%, and 3.3% for R=Mg, Ca, Sr, and Ba, respectively, because of the Jahn-Teller effect. The whole decreasing crystal-field strength Dq and orbital reduction factor k from Mg to Sr are ascribed to the weakening electrostatic coulombic interactions and the increasing probability of productivity of nonbridge oxygen (and hence increasing Cu2+–O2− electron cloud admixtures) under PbO addition, respectively, with increasing alkali earth ionic radius. The anomalies (the largest Dq and the next highest k among the systems) for R=Ba are attributed to the cross linkage of this large cation in the network. The overall increasing order (Mg≤Ba<Ca<Sr) of ρ is largely due to the decreasing crystal-field strength Dq and hence the decreasing force constant of the Cu2+–O2− bonds. The present studies would be helpful to understand local structures and the influences on the optical properties of RPPZ glasses containing copper dopants.

INVESTIGATIONS OF THE EPR PARAMETERS FORDy3+CENTER INZrSiO4CRYSTAL

2010 ◽  
Vol 24 (03) ◽  
pp. 289-296 ◽  
Author(s):  
HUI-NING DONG ◽  
DENG-FENG LI ◽  
JUN LIU ◽  
DAVID J. KEEBLE
Keyword(s):  
Crystal Field ◽  
Tetragonal Symmetry ◽  
Spin Orbit Coupling ◽  
Spin Hamiltonian ◽  
Field Interaction ◽  
Paramagnetic Resonance ◽  
Epr Parameters ◽  
Structure Constants ◽  
Hamiltonian Parameters ◽  
G Factors

The electronic paramagnetic resonance g factors g‖, g⊥of Dy3+centers and the hyperfine structure constants A‖and A⊥of161Dy3+and163Dy3+isotopes in ZrSiO4crystal are theoretically studied from the perturbation formulas of the spin Hamiltonian parameters for a 4f9ion in tetragonal symmetry. In these formulas, the contributions to g factors due to the J-mixing among the ground6H15/2, the first excited6H13/2and second excited6H11/2states via crystal-field interaction, the admixtures among the states with the same J value via spin-orbit coupling interaction and the interactions between the lowest Kramers doublet Γγ and other 20 Kramers doublets ΓXwithin the states6HJ(J=15/2, 13/2 and 11/2) via crystal-field and orbital angular momentum interactions are considered. The calculated EPR parameters show reasonable agreement with the observed values. The results are discussed.

Temperature Dependence of the Crystal-Field Splittings in Gd3+:CaWO4

1971 ◽  
Vol 49 (8) ◽  
pp. 995-1003 ◽  
Author(s):  
J. S. M. Harvey ◽  
H. Kiefte
Keyword(s):  
Electron Spin Resonance ◽  
Low Temperature ◽  
Crystal Field ◽  
Electron Spin ◽  
Fourth Order ◽  
Lattice Vibrations ◽  
Spin Hamiltonian ◽  
Spin Resonance ◽  
Crystal Field Parameters ◽  
Hamiltonian Parameters

The spin-Hamiltonian parameters for Gd3+ in CaWO4 have been measured by the method of electron spin resonance at a number of temperatures between 4.2 °K and 300 °K. The results at 78 °K are in agreement with previous measurements by Hempstead and Bowers.The variations in the crystal-field parameters are interpreted in terms of a limiting low temperature value and a normalized slope at the Debye temperature for each parameter. These quantities are compared with the corresponding quantities for Eu2+ in CaWO4 and, in the case of the fourth-order parameters, for Eu2+ and Gd3+ in cubic CaF2, SrF2, and BaF2. We conclude that the second- and fourth-order splittings each arise from at least three competing mechanisms and that these include a dependence on the amplitude of lattice vibrations. In the case of the trivalent ion, Coulomb forces are also considered to be important.

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