Measurement of the nuclear magnetic dipole moment of Au197 and hyperfine structure measurements in the ground states of Au197, Ag107, Ag109 and K39

Using an atomic beam magnetic resonance apparatus the nuclear magnetic dipole momentμ _I of the stable isotope Au¹⁹⁷ was measured directly with the doublet method. The result isμ _I(Au¹⁹⁷)=0.143491 (9)μ _n, uncorrected for atomic diamagnetism. Further hyperfine structure measurements were performed in the ground states of K³⁹, Ag¹⁰⁷, Ag¹⁰⁹ and Au¹⁹⁷ with the following results:Δv(K³⁹)=461.719723 (38) MHzΔv(Ag¹⁰⁷)=1712.512111 (18) MHzΔv(Ag¹⁰⁹)=1976.932075 (17) MHzΔv(Au¹⁹⁷)=6099.320184 (13) MHzg _J(Ag¹⁰⁷)/g _J(K39)=1.0000260 (20)g _J(Au¹⁹⁷)/g _J(K39)=1.0005076 (20).     

Precision measurement of the hyperfine structure of Lu175 with the atomic beam magnetic resonance method

The hyperfine structure separations of both doublet states² D _3/2 and² D _5/2 of the ground state configuration 6s ² 5d of Lu¹⁷⁵ have been remeasured with high precision using the atomic beam magnetic resonance method. Magnetic dipole transitions between Zeeman components of the hfs levels were induced applying Ramsey's technique of separated oscillatory fields whenever the field dependence of the resonances was small enough. The hfs intervals at zero field and hfs interaction constants were derived from the measurements. The constants were then corrected for hfs perturbations between the two levels of the doublet. Configuration interaction has been taken into account for the calculation of the dipole matrix elements. The corrected hfs constants are:J=3/2:A=194.332921 (300) MHzB=1511.396 267 (320) MHzC=?70 (19) HzJ=5/2:A=146.776 472 (138) MHzB=1860.656132 (840) MHzC=913 (162) HzD=?16 (24) Hz A quadrupole hfs anomaly between Lu¹⁷⁵ and Lu^176m was not found when comparing the following two ratios: Lu¹⁷⁵:B(5/2)/B(3/2)=1.2310850 (16) Lu^176m :B(5/2)/B(3/2)=1.2310818 (30). So far we have not succeeded in computing an octopole moment from the twoC-factors for the terms² D _3/2,5/2 because the influence of higher configurations could not sufficiently be considered.     

Hyperfine structure investigations in the4F9/2 atomic ground state of191Ir and193Ir

The5d ⁷6s^{2 4}F_9/2 atomic ground state of¹⁹¹Ir and¹⁹³Ir has been studied using the atomic-beam magnetic-resonance method. The results are:¹⁹³Ir:g _J(⁴F_9/2)=1.29694 (3)¹⁹¹Ir:Δv(⁴F_9/2; F=6?F=5)=659.26496 (12) MHzΔv( ⁴F_9/2; F=5?F=4)=189.44002 (09) MHzΔv( ⁴F_9/2; F=3?F=4)=84.05040 (80) MHzA=57.52148 (04) MHzB=471.20425 (57) MHzC=?0.020 (30) kHz¹⁹³Ir:Δv( ⁴F_9/2; F=6?F=5)=660.09043 (12) MHzΔv( ⁴F_9/2; F=5?F=4)=224.47848 (13) MHzΔv( ⁴F_9/2; F=?F=4)=33.53453 (89) MHzA=62.65556 (05) MHzB=426.23546 (64) MHzC=0.020 (30) kHz Using the magnetic dipole moments known by NMR-technique [1] we obtained for the electric quadrupole moments as calculated from the hyperfine interaction constantsA andB:Q(¹⁹¹Ir)=0.78 (20) barns,Q(¹⁹³Ir)=0.70 (18) barns (uncorrected for core polarization effects). A calculation of the hyperfine anomaly yields:₁₉₁ Δ ₁₉₃=?0.00023 (10). The ratio of theB factors which should be the same as for the quadrupole moments turned out to be:B(¹⁹¹Ir)/B(¹⁹³Ir)=Q(¹⁹¹Ir)/Q(¹⁹³Ir)=1.105502(3).     

Hyperfine structure investigations of some odd levels of Co I by level crossing and optical methods

Using the level crossing technique the ratios and absolute values of the hyperfine structure (hfs) constants of the levelsz ⁴F_9/2 andz ⁴F_7/2 of the configuration 3d ⁷4s4p of Co I were measured:z ⁴ F _9/2: ¦A¦=(811±12)MHz; ¦B¦=(48±93) MHz;B/A=?0.06±0.11 A>0; B<0z ⁴ F _7/2: ¦A¦ = (659 ±11)MHz; ¦B¦=(33±84)MHz;B/A=?0.05±0.13 A>0; B<0. In addition the hfs constants of three other excited levels of Co I could be determined by optical methods:z ⁴ F _9/2:A=525±26 MHz;B=200 MHzy ⁴ F _9/2:A=300±30 MHz;B=?500 MHzy ⁴ G _11/2:A=315±20 MHz;B=400 MHz. The experimental results are compared with known experimental and also with theoretical values which where calculated using the parametric potential method.     

Gleichzeitige Messung von Hyperfeinstruktur,Starkeffekt und Zeemaneffekt des85Rb19F mit einer Molekülstrahl-Resonanzapparatur

A molecular beam resonance apparatus with electric quadrupole lenses asA- andB-fields and with superimposed parallel electric and magnetic transition-fields was used. Molecules in different rotational statesJ, m _J are separated by theA-field. Spectra of molecules in different vibrational states are resolved by their different Starkeffect energies. By this means the following electric and magnetic properties of the molecule could be measured in the rotational stateJ=1 and vibrational statesv=0 and 1: The magnetic and electric dipole moment of the molecule, the scalar and the tensor nuclear dipole — dipole interactiond _s andd _T, the nuclear spinrotational interactionc _F andc _Rb, the nuclear quadrupole interactioneqQ, the nuclear magnetic moment μ_Rb, the anisotropy of the diamagnetic susceptibility ξ_⊥?ξ_∥, the anisotropy of the diamagnetic shielding of the external field by the electrons at the position of the nuclei σ_⊥?σ_∥. Using these quantities it was possible to calculate the quadrupole moment and a weighted quadrupole moment of the electronic charge distribution. The results are: (J=1,v=0) μ_el=8,5464 (17) debμ _J/J=?29,79(2)x10^?6 μ _B d _s/h=0,36(23) kHzd _T/h=0,69(22)kHzc _F/h=10,42(70) kHzc _Rb/h=0,479 (48) kHz.eqQ _Rb/h=?70,3410(26) MHzμ(1?σ_S)Rb=1,3474(5) μ_k (ξ⊥-ξ _∥)=12(6)×10^?30 erg/Gauß² (σ_⊥-σ∥)_Rb=?3,8(2,1)×10^?4 (σ⊥-σ _∥)_F=?2,6(3)×10^?4     

Measurement of the nuclear quadrupole moment of53Cr by laser-Rf double resonance

The hyperfine structure of the metastable atomic states (3d ⁴4s ²)⁵ D _1,2,3,4 of⁵³Cr has been measured using theABMR-LIRF method (atomic beam magnetic resonance detected by laser induced resonance fluorescence). The dipole coupling constantsA and the quadrupole coupling constantsB are found to beA(⁵ D ₁)=?17.624(2) MHzB(⁵ D ₁)=?21.847(5) MHzA(⁵ D ₂)=?25.113(2) MHzB(⁵ D ₂)=?13.485(5) MHzA(⁵ D ₃)=?35.683(2) MHzB(⁵ D ₃)=15.565(5) MHzA(⁵ D ₄)=?48.755(2) MHzB(⁵ D ₄)=63.021(5) MHz. From these measured hfs constants the electric quadrupole moment for⁵³Cr is calculated to beQ=?0.15 (5) barn. The 30% error takes into account the uncertainties due to configuration interaction effects (shielding and antishielding effects) and of deviations from pure SL-coupling for the states⁵ D _1,2,3,4.     

Hyperfine-structure investigation in the 6s5d configuration of135Ba and137Ba

The hyperfine structure of the metastable states of the 6s5d configuration of¹³⁵Ba and¹³⁷Ba has been studied by the atomic-beam magnetic resonance (ABMR) method. The metastable barium states were populated in a plasma-discharge inside the atomic-beam oven. The atoms emerging from the ABMR-apparatus were detected by the use of a dyelaser. Compared to conventional methods this technique has the advantage of being state selective. The following magnetic dipole and electric quadrupole interaction constantsa andb have been obtained:¹³⁷Ba:a(³ D ₁)=?520.536 (3) MHzb(³ D ₁)=17.890 (3) MHza(³D₂=415.928 (3) MHzb(³D₂)=25.899 (13) MHza(³D₃)=456.559 (4) MHzb ³D₃=47.390 (16) MHz¹³⁵Ba:a ³ D ₁=?465.166 (4) MHzb(³D₁)=11.642 (4) MHza(³D₂)=371.736(4) MHzb ³ D ₂=16.745 (14) MHza(³D₃)=408.038 (6) MHzb(³D₃)=30.801 (24) MHz Using these constants and the earlier known ones for the¹ D ₂ state the hyperfine structure for the 6s5d configuration has been analyzed with an effective hyperfine hamiltonian. Hyperfine parameters obtained from the analysis have been compared with theoretical values calculated with relativistic self-consistent-field (SCF) wavefunctions. The quadrupole moments have been evaluated with the following result Q(¹³⁵Ba) =0.20(3)b and Q(¹³⁷Ba) = 0.34(4)b uncorrected for the quadrupole shielding.     

Hyperfine structures and isotope shifts of the 5d 4 D 7/2→6p 4 P 5/2 0 transition in Xenon ions

Collinear fast beam-laser spectroscopy has been performed on metastable 5d ⁴ D _7/2 Xenon ions. Hyperfine structure constants for the 6p ⁴ P _5/2 ⁰ level have been derived for¹²⁹Xe:A=?1,634.9±0.9 MHz and¹³¹Xe:A=485.3±0.3 MHz andB=?116.5±2.0MHz. Changes in mean squared nuclear charge radii are derived from the measured isotope shifts.     

Hexadecapole interaction in the atomic ground state of165Ho

Using the atomic beam magnetic resonance method several hyperfine transitions in the ground state of¹⁶⁵Ho were measured at magnetic fields near zero Oe. Including a hexadecapole interaction constantD a perfect fit of the seven hyperfine separations was possible giving the following results:A′=800.583645 (6)MHz,C′=?1.504 (37)kHzB′=?1668.00527 (33)MHz,D′=?0.137 (14)kHz. These interaction constants have been corrected for second order hyperfine interaction within the⁴I ground multiplet. The corrected constants are the following:A=800.583173 (36)MHz,C=?0.249 (140)kHzB=?1668.078 70 (330) MHz,D=?0.148 (16) kHz. Using a value for 〈r _4f ^/?5 〉_Ho of Fraga a nuclear hexadecapole moment can be calculated:Π(¹⁶⁵Ho)=0.89·10^?48cm⁴. Because of severe uncertainties still present in the theory for calculating the electronic matrix elements this value can be only regarded as highly speculative.     

Bestimmung von Moleküleigenschaften des Tl205F19 aus kombinierten Stark-Zeeman-Effekt-Messungen mit der Molekularstrahlmethode

An electric Molecular-Beam-Resonance-Spectrometer has been used to measure simultanously the Zeeman- and Starkeffect splitting of the hyperfinestructure of TlF. Electric fourpole lenses served as focusing and refocusing fields of the spectrometer. A homogenous magnetic field (Zeeman-Field) was superimposed to the electric field (Stark-Field) in the transition region of the apparatus. The observedΔm _J =±1 -transitions were induced electrically. Completely resolved spectra of Tl²⁰⁵F¹⁹ in theJ=1 rotational, andυ=0 vibrational state have been measured. The obtained quantities are: The rotational magnetic momentμ _J of Tl²⁰⁵F¹⁹ in the stateJ=1,υ=0, and the difference of the magnetic shielding (σ _1,±1?σ _1,0) of both nuclei as well as the difference of the molecular susceptibility (ξ _1,±1?ξ _1,0) in the states (J, m _J)=(1,±1) and (J, m_J)=(1, 0). The sign of the rotational magnetic moment could be determined unambigously by the influence of offdiagonal matrix elements. The numerical values for Tl²⁰⁵F¹⁹ in the stateJ=1 andυ=0 are:μ _J =?29,153(21) · 10^?6 μ _Bohr (σ _1,±1?σ _1,0)^Tl=?0,002291 (33) (σ _1,±1?σ _1,0)^F=?0,000206(9) (ξ _1,±1-ξ _1,0)=+3,02(15) · 10^?30erg/Gauß² The quantities in brackets are root-mean-square deviations in units of the last digit. From these data and the known values for the spin-rotational interaction constants a number of expressions are derived which characterise the electronic charge distribution in the molecule.     

Mesure de la structure hyperfine du niveau 3s2 DE 21Ne

We describe a level-crossing measurement of the hyperfine structure of the 3s₂ level of ²¹Ne optically pumped by a laser beam. The magnetic dipole and electric quadrupole hyperfine interaction constants a and b are obtained: a = -728.0±0.8 MHz, b=-13.4±2.5 MHz.     

Ground-State hyperfine structure and nuclear magnetic moment of Thulium-169

The hyperfine structure of the 4f ¹³ 6s ^{2 2} F _7/2 ground state of Tm¹⁶⁹ has been studied with the atomic beam magnetic resonance method. By measuring strongly field-dependent transitions in external magnetic fields between 2200 and 3000 Gauss the interaction between the nuclear magnetic dipole momentμ _I and the external field was determined. These measurements yielded a direct value forμ _I independent of the electronic properties of the Tm-atom. The results are:μ _I=? 0.2310 (15)μ _n (diamagnetically corrected), magnetic dipole interaction constanta=? 374.137661(3) Mc/sec andg _J(4f ¹³ 6s ^{2 2} F _7/2)=1.141189 (3).     

High precision measurements of the hyperfine structure of seven metastable atomic states of57Fe by laser-Rf double-resonance

The hyperfine structure of the metastable atomic states (3d ⁷4s)⁵ F _2,3,4,5 and (3d ⁷ 4s)³ F _2,3,4 of⁵⁷Fe has been measured using theABMR- LIRF method (atomic beam magnetic resonance detected by laser induced resonance fluorescence). From these measurements the following hfs constantsA of the magnetic dipole interaction have been obtained (corrected for second order effects):A(⁵ F ₂)=55.994(7) MHzA(⁵ F ₃)=69.632(5) MHzA(⁵ F ₄)=78.435(4) MHzA(⁵ F ₅)=87.246(3) MHzA(³ F ₂)=143.328(4) MHzA(³ F ₃)=50.602(10) MHzA(³ F ₄)=13.456(5) MHz     

Bestimmung des elektrischen Kernquadrupolmomentes des ungeraden stabilen Strontium-87-Kerns

In order to determine the electric quadrupole moment of Sr⁸⁷ (I= 9/2) the hyperfine structure-splitting of the 5s5p ³ P ₁-state of the SrI-spectra was investigated by optical double resonance. By detection of high frequency transitions (ΔF=±1,Δm _F=0,±1) in an external magnetic fieldH ₀≈0 one obtains the hyperfine structure separations asv _F=11/2?F=9/2=1463·149 (6) Mc/sec andv _F=9/2?F=7/2=1130·264 (6) Mc/sec. From these frequencies one calculates the magnetic hyperfine structure-splitting constantA=?260·084 (2) Mc/sec and the electric quadrupole interaction constantB=?35·658 (6) Mc/sec. B leads to an electric quadrupole moment ofQ(Sr⁸⁷)=+0·36 (3)·10^?24 cm².     

Optical absorption spectrum and crystal field of erbium aluminum garnet (ErAlG)

The optical absorption spectrum of Erbium Aluminum Garnet (ErAlG) has been measured between 12000 cm^?1 and 26000 cm^?1. The crystal field splitting of the terms⁴I_15/2,⁴I_9/2,⁴F_9/2,⁴S_3/2,²H_11/2,⁴F_7/2,⁴F_5/2,⁴F_3/2,²H_9/2 and⁴G_11/2 was determined from the spectra and has been analysed in terms of the usual parametrization scheme. Nine crystal field parametersA _l ^m 〈r ^l〉≡B _l ^m which are necessary to describe the crystal field with the symmetryD ₂ at the site of the rare earth ion, were fitted to the experimental data. The values are (in cm^?1):B ₂ ⁰=+160B ₄ ⁰=?160B ₆ ⁰=+30B ₆ ⁶=+80B ₂ ²=?100B ₄ ²=+140B ₂ ⁶=?40B ₄ ⁴=?1800B ₆ ⁴=?700 This result is compared with those obtained from similar analysis of other garnets.     

Nuclear magnetic resonance on oriented194Ir (T 1/2=19.4 h) in Fe and Ni

The hyperfine interaction of¹⁹⁴Ir (j ^π =1^?;T _1/2=19.4 h) in Fe and Ni has been investigated with the technique of nuclear magnetic resonance on oriented nuclei. For both systems the electronic-orbital-momentum induced electric quadrupole splitting could be resolved. The magnetic and electric hyperfine splitting frequencies,v _M =¦gμ _N ^B _HF/h¦ andv _Q =e ² qQ/h, respectively, were measured as:¹⁹⁴IrFe:v _m =408.54 (23) MHz;v _q =?2.47(20) MHz;¹⁹⁴IrNi:v _M =135.24(5) MHz;v _q =?1.23 (3) MHz. Taking into account a 3% uncertainty arising from hyperfine anomalies theg-factor is deduced as ¦g¦=0.39 (1). The electric quadrupole moment,Q=+0.352 (18)b, is slightly smaller than expected from the known systematics of deformation parameters in this mass region.     

Hyperfine structure measurements in the ground states5 F 5,5 F 4,5 F 3 and5F2 of99Ru and101Ru with the atomic beam magnetic resonance method

The hyperfine structure of the four lowest levels⁵ F _{5, 4, 3, 2} of the⁵ F ground state multiplet arising from the configuration 4d ⁷ 5s in⁹⁹Ru and¹⁰¹Ru has been studied by the atomic — beam magnetic — resonance technique. After applying corrections due to the effects of off-diagonal hyperfine mixing we obtain the following multipole interaction constants:⁹⁹Ru:A(⁵ F ₅)=?204.5514(33) MHzB(⁵ F ₅)=27.281 (62) MHzA ⁵ F ₄=?163.6845(36) MHzB(⁵ F ₄)=17.455(52) MHzA ⁵ F ₃=?135.0294(37) MHzB(⁵ F ₃)=10.164(50) MHzA(⁵ F ₂)=? 82.5325(27) MHzB(⁵ F ₂)=5.457(22) MHz¹⁰¹Ru:A(⁵ F ₅)=?229.2881(33) MHzB(⁵ F ₅)=158.934(62) MHzA(⁵ F ₄)=?183.4744(36) MHzB(⁵ F ₄)=101.799(52) MHzA(⁵ F ₃)=?151.3502(38) MHzB(⁵ F ₃)=59.323(50) MHzA(⁵ F ₂)=?92.4974(27) MHzB(⁵ F ₂)=31.869(23) MHz. The magnetic dipole and the electric quadrupole moments of the⁹⁹Ru and¹⁰¹Ru nuclear ground states as calculated from these constants are the following:μ _I (⁹⁹Ru)=?0.594(119) nmQ(⁹⁹Ru)=0.077 (15) barnsμ _I (¹⁰¹Ru)=?0.666(133)nmQ(¹⁰¹Ru)=0.45 (9) barns. From measurements of the Zeeman effect in the even isotope¹⁰²Ru we find the followingg _J -factors for the⁵ F ground multiplet:g _J (⁵ F ₅)=1.397741(20)g _J (⁵ F ₄)=1.347604(20)g _J (⁵ F ₃)=1.248988(20)g _J (⁵ F ₂)=1.001120(3).     

Hyperfeinstrukturuntersuchung der 4p und 5p 2 P 3/2-Terme im K I-Spektrum durch Resonanzstreuung von Licht zur Bestimmung der Kernquadrupolmomente von K39 und K41

In order to determine the nuclear quadrupol moments of the stable K-isotopes, the hyperfine structure of the 4p and5p ²P_3/2-states was investigated by resonance scattering of light. The scattered intensityR(H) from separated isotopes in a sealed off resonance cell, as function of an external magnetic fieldH was observed with different polarisations (σ- andπ-components perpendicular toH) both in exciting and scattered light. Because the hfs-splitting of the investigated states is comparable to the radiation widthГ, the measured change in intensityΔR(H)/ΔH is due to interference effects (Hanle-effect, level-crossing, anti-crossing) and decoupling of electronic and nuclear spin (Heydenburg-effect). The different effects are not distinguishable in contrary to an usual level-crossing experiment and therefore the measured signal-structure is compared with line shape calculations according to Breit's-formula. Assuming “white” excitation andg _J =4/3, the measured signal-structure can be explained with the following values:Γ/2π (4p)=5.7 (4) MHzΓ/2π (4p)=5.7 (4) MHz K³⁹:A(4p)=6.13(5) MHzB(4p)=2.72(12) MHzA(5p)=1.97(2) MHzB(5p)=0.85 (3) MHz K⁴¹:A(4p)=3.40(8) MHzB(4p)=3.34(24) MHzA(5p)=1.08(2) MHzB(5p)=1.06 (4) MHz. Without Sternheimer corrections one obtains from these values Q(K³⁹)=0.062 · 10^?24 cm² and Q(K⁴¹)=0.076 · 10^?24 cm² for the electrical nuclear quadrupolmoments of K³⁹ and K⁴¹.     

Bestimmung der Kernmomente des Ho165 aus der Hyperfeinstruktur des Grundzustandes im Ho I-Spektrum

In an atomic beam magnetic resonance experiment, the hyperfine interaction constantsA andB of the⁴ I _2/15-groundstate of Ho¹⁶⁵ were found to beA=800,58389 (50) MHz,B=?1667,997 (50) MHz. Using an effective value for 〈r ^?3〉, the magnetic moment of the Ho¹⁶⁵ nucleus was calculated to beμ=4·1(4)μ _n . The quadrupolement was determined by use of the 〈r ^?3〉 given byWatson andFreeman. The result isQ=2·4·10^?24 cm².     

The crystal structure of bis-(L-threonine) copper(II).H2O

The crystal structure of bis-(L-threonine) copper (II).H₂O, Cu (C₄H₈NO₃)₂.H₂O has been determined by heavy atom and Fourier methods and refined by least-squares using visually estimated three-dimensional x-ray data of 893 reflections. The blue crystals are monoclinic, space groupP2₁ withα=11·02,b=4·90,c=11·16Å andβ=93·5°,Z=2. The finalR is 0·10. Coordination of copper is distorted square pyramidal with ligands intrans configuration. The conformation of one of the aminoacid ligand is identical with L_s-Threonine while the other has a conformation with torsional angleχ ^{1, 2}=?74(1)°.