Isotope shift and hyperfine structure in the atomic spectrum of tin

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.

The lines λ340.5 nm, λ357.1 nm, and λ677.4 nm of the arc spectrum of palladium have been studied under high resolution by means of digital recording interferometry. The even-even shifts are claimed to be more accurate than previously published work; the relative shifts determined in λ357.1 nm are 102 Pd - 104 Pd, 1.03(2); 104 Pd - 106 Pd, 1.00; 106 Pd - 108 Pd, 1.02(1); 108 Pd - 110 Pd, 0.92(2); 104 Pd - 105 Pd, 0.23(1). An odd-even shift has been measured for the first time in this element, and shows appreciable staggering. The relative shift 102 Pd - 104 Pd has been found to be substantially greater than the values reported in the literature. Values of the change in the mean square radius of the nuclear charge distribution have been deduced from the measurements, all to an accuracy of Ŧ15% ; these are: 102 Pd - 104 Pd, 0.176 fm 2 ; 104 Pd - 106 Pd, 0.170 fm 2 ; 106 Pd - 108 Pd, 0.173 fm 2 ; 108 Pd - 110 Pd, 0.153 fm 2 .


2013 ◽  
Vol 337-338 ◽  
pp. 49-53
Author(s):  
Min Quan Kuang ◽  
Shao Yi Wu ◽  
Xian Fen Hu ◽  
Bo Tao Song

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.


The isotope shifts in the spark line λ 4416 of cadmium (4 d 10 5 p 2 P 3/2 ─4 d 9 5 8 2 2 D 3/2 ) are accurately measured by means of single and double Fabry─Perot etalons and with the use of electromagnetically enriched isotopes. The shifts between successive even isotopes are found to decrease with increasing neutron number in an irregular manner. Accurate values are obtained for the odd-even and odd-odd shifts in λ 4416; this involved the study of the h. f. s. of the lines λ 3250 and λ 3535. Pronounced odd-even staggering is found. Some conclusions on the change of nuclear deformation with neutron number are drawn and possible connexions with shell structure discussed.


The hyperfine structure of the ground state 4 f 7 6 s 2 8 S 7/2 of 151 Eu and 153 Eu has been measured by the method of magnetic resonance in an atomic beam. The sign of the hyperfine structure and the value of g J have also been measured. The results are: g J = 1·9935 ± 0·0003; A (151) = -20·0523 ± 0·0002 Mc/s, A (153) = -8·8532 ± 0·0002 Mc/s, B (151) = - 0·7012 ± 0·0035 Mc/s, B (153) = - 1·7852 ± 0·0035 Mc/s; A (151)/ A (153) = 2·26498 ± 0·00008, B (151)/ B (153) = 0·393 + 0·003. These results disagree with the values expected for the pure 8 S 7/2 state formed from a half-filled shell of f -electrons. Calculations on the basis of admixture of higher states of the configuration by spin-orbit coupling account for the discrepancy in g J but do not explain the values of the hyperfine structure constants A and B . Further theoretical work is in progress.


Atoms ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 39 ◽  
Author(s):  
Elena Konovalova ◽  
Yuriy Demidov ◽  
Mikhail Kozlov ◽  
Anatoly Barzakh

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.


1970 ◽  
Vol 25 (5) ◽  
pp. 611-620 ◽  
Author(s):  
L. H. Göbel

The magnetic dipol and the electric quadrupol interaction constants in the excited electronic states 5d6s6p (1D) 2D3/2 and 5d6s6p (1D) 2F5/2 of 175Lu I in natural isotopic abundance were investigated. The measurement was performed by resonance scattering of light with wavelengths λ = 4518.57 Å and λ = 3567.84 Å on a lutetium atomic beam. The following hyperfine structure constants were obtained:B/A{(1D) 2D3/2} = +0.34704(80) ; A{(1D) 2D3/2} =-1313.34(50) gJ/0.80 MHz; B{(1D) 2D3/2} =- 455.8(1.2) gJ/0.80 MHz; B/A{(1D) 2F5/2} = +9.7883(37) ; A{(1D) 2F5/2} =+ 351.864(56) gJ MHz; B{(1D) 2F5/2} = + 3444.2 (1.9) gJ MHz.The signs of the interaction constants were determined by examinations of these lines in a Fabry- Perot-interferometer. The lifetimes of the investigated states were found as follows:τ{(1D) 2D3/2} = (4.9 ± 0.1) · 10-8 s; τ{(1D) 2F5/2) = (1.2 ± 0.1) · 10-8 s.From these the oscillatorstrengths were deduced:ƒ(3567.8 Å) = (1.7 + 0.2) · 10-1; ƒ(3841.2 Å) = (5.6 + 0.8) · 10-2;ƒ(4518.6 Å) = (6.3 ± 0.1) · 10-2; ƒ(4967.5 Å) < 3 · 10-4.


2013 ◽  
Vol 68 (6-7) ◽  
pp. 442-446 ◽  
Author(s):  
Min-Quan Kuang ◽  
Shao-Yi Wu ◽  
Xian-Fen Hu ◽  
Bo-Tao Song

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.


2000 ◽  
Vol 55 (5) ◽  
pp. 539-544 ◽  
Author(s):  
Wen-Chen Zheng ◽  
Shao-Yi Wu

Abstract The formulas of the g-factors gII , g┴ and the hyperfine structure constants AII.A┴ for 3d7 ions in tetragonal octahedral crystals are established from a cluster approach. Differing from previous formulas, in these formulas the role of configuration interaction (CI)-and covalency (CO)-effects is considered, and the parameters related to both effects are obtained from the optical spectra and the structural parameters of the studied crystal. From these formulas, the EPR parameters gi and Ai for K2 ZnF4 :Co2+ are calculated. The results show good agreement with the observed values. The contributions to the EPR parameters gi and Ai, from the CI and CO effects, and the relationship between the sign of Δg(=g┴ - gII) and the tetragonal distortion (elongated or compressed) of the ligand octahedron are discussed


2008 ◽  
Vol 22 (14) ◽  
pp. 1381-1387 ◽  
Author(s):  
XUE-FENG WANG ◽  
SHAO-YI WU ◽  
ZHI-HONG ZHANG ◽  
LI-HUA WEI ◽  
YUE-XIA HUA

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.


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