Studies of Knight Shifts and Hyperfine Structure Constants of Tl2Ba2CuO6+y

2013 ◽  
Vol 337-338 ◽  
pp. 49-53
Author(s):  
Min Quan Kuang ◽  
Shao Yi Wu ◽  
Xian Fen Hu ◽  
Bo Tao Song
Keyword(s):  
Hyperfine Structure ◽  
Local Structure ◽  
High Order ◽  
Order Perturbation ◽  
Calculation Results ◽  
Structure Constants ◽  
Knight Shifts ◽  
Good Agreement

The Knight shifts and hyperfine structure constants of Tl2Ba2CuO6+yare theoretically studied from the high order perturbation formulas of these quantities for a tetragonally elongated octahedral 3d9cluster. The calculation results reveal good agreement with the observed values. The obvious anisotropies of the Knight shifts can be ascribed to the local tetragonal elongation of the Cu2+site. The results and the local structure of the system are discussed.

Theoretical investigations of 63Cu2+ orbital Knight shifts for YBa2Cu4O8

2015 ◽  
Vol 29 (25n26) ◽  
pp. 1542007 ◽  
Author(s):  
Min-Quan Kuang ◽  
Shao-Yi Wu ◽  
Zhi-Hong Zhang ◽  
Xian-Fen Hu
Keyword(s):  
Experimental Data ◽  
Experimental Verification ◽  
High Order ◽  
Order Perturbation ◽  
Theoretical Investigations ◽  
Calculation Results ◽  
Knight Shifts ◽  
Good Agreement

The temperature-independent orbital Knight shifts for the orthorhombic [Formula: see text] site in [Formula: see text] (Y124) are investigated by utilizing the high order perturbation formulae of these parameters for a [Formula: see text] ion situated into orthorhombically elongated octahedra. The calculation results are in good agreement with the experimental data. The moderate quasi-axial anisotropies of the Knight shifts are ascribed to the elongation distortion of the four-fold coordinated Cu[Formula: see text] site. The [Formula: see text] factors are also theoretically calculated in a uniform way for further experimental verification.

Theoretical Investigations of the Knight Shifts and the Hyperfine Structure Constants for the Tetragonal Cu2+ Sites in the Bismuth- and Thallium-Based High-Tc Superconductors

2013 ◽  
Vol 68 (6-7) ◽  
pp. 442-446 ◽  
Author(s):  
Min-Quan Kuang ◽  
Shao-Yi Wu ◽  
Xian-Fen Hu ◽  
Bo-Tao Song
Keyword(s):  
Hyperfine Structure ◽  
High Tc Superconductors ◽  
Paramagnetic Resonance ◽  
High Tc ◽  
Theoretical Investigations ◽  
Calculation Results ◽  
Structure Constants ◽  
Knight Shifts ◽  
Electron Paramagnetic ◽  
Good Agreement

The Knight shifts and hyperfine structure constants for the tetragonal Cu2+ sites in bismuth- and thallium-based high-Tc uperconductors ( Bi1:6Pb0:4Sr2Ca2Cu3O10, TlSr2CaCu2O7-y, and Tl2Ba2CuOy) are theoretically investigated from the high-order perturbation formulas of these parameters for a 3d9 ion under tetragonally elongated octahedra in a unified way. The calculation results show good agreement with the observed values. The significant anisotropies of the Knight shifts are attributed to the local tetragonal elongation distortions of the five-(or six-)coordinated Cu2+ sites in these systems. The present studies would be beneficial to establish a complete physical scheme for unified understandings of electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectral behaviours of Cu2+ (or other similar 3d9 ions) in the high-Tc superconductors.

Theoretical studies on the Knight shifts for the tetragonal Cu2+ site in HgBa2CuO4+δ

2015 ◽  
Vol 29 (25n26) ◽  
pp. 1542020
Author(s):  
Guo-Liang Li ◽  
Shao-Yi Wu ◽  
Min-Quan Kuang ◽  
Xian-Fen Hu
Keyword(s):  
Local Structure ◽  
High Order ◽  
Order Perturbation ◽  
Theoretical Studies ◽  
Copper Site ◽  
Calculation Results ◽  
Knight Shifts

The Knight shifts for the tetragonal [Formula: see text] site in [Formula: see text] are theoretically studied from the high order perturbation formulas of the Knight shifts for a tetragonally elongated octahedral [Formula: see text] cluster. The significant anisotropy of the Knight shifts is attributable to the obvious tetragonal elongation distortion of the [Formula: see text] site. The anisotropic [Formula: see text] factors of this system are uniformly analyzed, and the calculation results and the local structure of the copper site are also discussed.

Investigation of the Spin Hamiltonian Parameters of Yb3+ in CaWO4 Crystal

2004 ◽  
Vol 59 (12) ◽  
pp. 943-946 ◽  
Author(s):  
Hui-Ning Dong ◽  
Shao-Yi Wu
Keyword(s):  
Hyperfine Structure ◽  
Local Structure ◽  
Reasonable Agreement ◽  
Second Order ◽  
Order Perturbation ◽  
Superposition Model ◽  
Spin Hamiltonian ◽  
Structure Constants ◽  
Hamiltonian Parameters ◽  
G Factors

In this paper, the spin Hamiltonian parameters g factors g∥ and g⊥ of Yb3+ and hyperfine structure constants A∥ and A⊥ of 171Yb3+ and 173Yb3+ in CaWO4 crystal are calculated from the two-order perturbation formulae. In these formulae, the contributions of the covalence effects, the admixture between J =7/2 and J =5/2 states as well as the second-order perturbation are included. The needed crystal parameters are obtained from the superposition model and the local structure of the studied system. The calculated results are in reasonable agreement with the observed values. The results are discussed.

STUDIES ON THE LOCAL STRUCTURE AND THE SPIN HAMILTONIAN PARAMETERS FOR THE TRIGONAL Mn2+ CENTER IN Bi4Ge3O12

2008 ◽  
Vol 22 (14) ◽  
pp. 1381-1387 ◽  
Author(s):  
XUE-FENG WANG ◽  
SHAO-YI WU ◽  
ZHI-HONG ZHANG ◽  
LI-HUA WEI ◽  
YUE-XIA HUA
Keyword(s):  
Hyperfine Structure ◽  
Local Structure ◽  
Zero Field ◽  
Spin Hamiltonian ◽  
Zero Field Splitting ◽  
Trigonal Symmetry ◽  
Oxygen Octahedron ◽  
Structure Constants ◽  
Hamiltonian Parameters ◽  
Good Agreement

The local structure and the spin Hamiltonian parameters (the zero-field splitting D, the g factors g//, g⊥ and the hyperfine structure constants A// and A⊥) for the trigonal Mn 2+ center in Bi 4 Ge 3 O 12 are theoretically studied from the perturbation formulas of these parameters for a 3d5 ion in trigonal symmetry. The impurity Mn 2+ replacing host Bi 3+ is not found to occupy the exact Bi 3+ site but to suffer a large off-center displacement by about 0.36 Å towards the center of the oxygen octahedron along the C3-axis due to the size and charge mismatching substitution. The calculated spin Hamiltonian parameters based on the above displacement show good agreement with the observed values. The results and the mechanism of the impurity displacement are discussed.

Isotope shift and hyperfine structure in the atomic spectrum of tin

1973 ◽  
Vol 332 (1588) ◽  
pp. 129-138 ◽  
Keyword(s):  
Stable Isotopes ◽  
Hyperfine Structure ◽  
Nuclear Charge ◽  
Light Sources ◽  
Atomic Spectrum ◽  
Nuclear Charge Distribution ◽  
Fabry Perot ◽  
Self Consistent ◽  
Structure Constants ◽  
Good Agreement

Three lines in the atomic spectrum of tin, λ 3262 Å, λ 3283 Å and λ 6454Å have been studied in emission under high resolution with the use of light sources containing enriched isotopic samples. Results are reported for isotope shifts in these lines for the abundant stable isotopes ( A ≽ 116). Pressure-scanned Fabry–Perot etalons provided the necessary resolution; the spectrograms for λ 6454 Å were recorded and analysed by digital techniques, and for this line hyperfine structure constants required in the interpretation of the data were also evaluated. The results for the three lines are not in good agreement with earlier work, but are shown to be self-consistent by means of a King plot. Their interpretation in terms of the nuclear charge distribution is considered in the following paper.

INVESTIGATIONS OF THE SPIN HAMILTONIAN PARAMETERS AND THE LOCAL STRUCTURE FOR THE RHOMBICCu2+CENTER IN RUTILE

2010 ◽  
Vol 24 (22) ◽  
pp. 2357-2364 ◽  
Author(s):  
HUA-MING ZHANG ◽  
SHAO-YI WU ◽  
PEI XU ◽  
LI-LI LI
Keyword(s):  
Local Structure ◽  
Impurity Center ◽  
Angular Distortion ◽  
Spin Hamiltonian ◽  
Rhombic Distortion ◽  
Calculation Results ◽  
Jahn Teller ◽  
Jahn Teller Effect ◽  
Structure Constants ◽  
Hamiltonian Parameters

The spin Hamiltonian parameters (the anisotropic g factors and the hyperfine structure constants) and the local structure for the rhombic Cu2+center in rutile ( TiO2) are theoretically investigated using the formulas of these parameters for a 3d9ion in rhombically elongated octahedra. From the studies, the planar impurity-ligand bond angle is found to be about 5.8° larger than that for the host Ti4+site due to the Jahn–Teller effect via bending the planar Cu2+– O2-bonds, which yields much smaller rhombic distortion in the impurity center. The theoretical spin Hamiltonian parameters based on the above local angular distortion show good agreement with the experimental data, and the improvement of the calculation results are also achieved as compared with those of the previous works.

Theoretical Studies of the Local Structures and EPR Parameters for the Rhombic Cu2+ Center in Cu0.5Zr2(PO4)3 Phosphate

2015 ◽  
Vol 70 (7) ◽  
pp. 553-557
Author(s):  
Li Chao-Ying ◽  
Huang Ying ◽  
Tu Qiu
Keyword(s):  
Local Structure ◽  
Bond Angle ◽  
Theoretical Studies ◽  
Paramagnetic Resonance ◽  
Local Structures ◽  
Epr Parameters ◽  
Structure Constants ◽  
Electron Paramagnetic ◽  
Distortion Angle ◽  
Good Agreement

AbstractThe local structure of the rhombic Cu2+ center in Cu0.5Zr2(PO4)3 phosphate is investigated by using the high-order perturbation formulas of electron paramagnetic resonance (EPR) parameters, g-factors gi (i=x, y, z), and hyperfine structure constants Ai for 3d9 ions in rhombically elongated octahedral symmetry. According to the studies, the local axial distortion angle Δα (≈ 5.1°) and the planar bond angle θ (≈ 83.8°) in [CuO6]10- cluster was obtained. The theoretical EPR parameters based on the aforementioned local structure parameters show good agreement with the observed values, and some improvement have been made as compared with the previous studies.

scholarly journals Calculation of Francium Hyperfine Anomaly

Atoms ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 39 ◽  
Author(s):  
Elena Konovalova ◽  
Yuriy Demidov ◽  
Mikhail Kozlov ◽  
Anatoly Barzakh
Keyword(s):  
Hyperfine Structure ◽  
Principal Quantum Number ◽  
Many Body ◽  
Experimental Accuracy ◽  
Hartree Fock ◽  
Many Body Perturbation Theory ◽  
Structure Constants ◽  
Analytical Expressions ◽  
Weakly Dependent ◽  
Good Agreement

The Dirac–Hartree–Fock plus many-body perturbation theory (DHF + MBPT) method has been used to calculate hyperfine structure constants for Fr. Calculated hyperfine structure anomaly for hydrogen-like ion is in good agreement with analytical expressions. It has been shown that the ratio of the anomalies for s and p1/2 states is weakly dependent on the principal quantum number. Finally, we estimate Bohr–Weisskopf corrections for several Fr isotopes. Our results may be used to improve experimental accuracy for the nuclear g factors of short-lived isotopes.

INVESTIGATIONS ON THE SPIN HAMILTONIAN PARAMETERS FOR Nd3+ IN ThGeO4

2007 ◽  
Vol 21 (02) ◽  
pp. 191-197
Author(s):  
SHAO-YI WU ◽  
HUI-NING DONG
Keyword(s):  
Hyperfine Structure ◽  
Second Order ◽  
Experimental Results ◽  
Order Perturbation ◽  
Tetragonal Symmetry ◽  
Theoretical Studies ◽  
Spin Hamiltonian ◽  
Structure Constants ◽  
Hamiltonian Parameters ◽  
G Factors

The spin Hamiltonian parameters, g factors g‖ and g⊥, for Nd 3+ in ThGeO 4 are theoretically investigated from the perturbation formulas of the g factors for a 4f3 ion in tetragonal symmetry. In these formulas, the contributions to the g factors from the second-order perturbation terms and the admixture of various states are taken into account. It is found that the calculated g factors of this work are smaller than the experimental results, but close to those in the previous theoretical studies by Gutowska et al. Moreover, the calculated hyperfine structure constants A‖ and A⊥ as well as the energies of the 4I9/2 Stark levels in this work are also consistent with those in the previous investigations. The discrepancy between theoretical and experimental g factors is discussed.

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