Influence of the core polarization on the dielectric properties of polyvalent metals

1998 ◽  
Vol 6 (3) ◽  
pp. 323-328 ◽  
Author(s):  
M. Knupfer ◽  
K. Widder ◽  
M. Sing ◽  
O. Knauff ◽  
J. Fink
Keyword(s):  
Dielectric Properties ◽  
Core Polarization ◽  
The Core

scholarly journals O2 State in 18 O by using Core – Polarization effects

2008 ◽  
pp. 66-72
Keyword(s):  
Perturbation Theory ◽  
Experimental Studies ◽  
Form Factors ◽  
Wave Model ◽  
Collective Model ◽  
Core Polarization ◽  
Polarization Effects ◽  
The Core ◽  
The Subject ◽  
Space Wave

Coulomb form factors for E0 transition in 18O are discussed taking into account core-polarization effects. These effects are taken into account through the collective model of Tassie and also through a microscopic perturbation theory including excitations up to 2p1f shell. Space wave model functions defined for the orbits 1 and 2125O nucleus has been the subject of extensive theoretical and experimental studies, which received much attention in last decade [Alex Brown et.al.2005]. The 18O system contains two neutrons in addition to the16O core distributed in the sd – shell. d1 are obtained from the diagonalization of the interaction Hamilonian of Wildenthal. The calculations include the 0 2state with excitation energies3.6337MeV. The core – polarization effects which incorporate the ollective model of Tassei describe the data very well for this state.

Calculation of the Knight Shift in Palladium

1979 ◽  
Vol 34 (4) ◽  
pp. 523-524 ◽  
Author(s):  
R. Krieger ◽  
J. Voitländer
Keyword(s):  
Fermi Surface ◽  
Knight Shift ◽  
Enhancement Factor ◽  
Negative Contribution ◽  
Core Polarization ◽  
Conduction Electrons ◽  
The Core ◽  
Core Electrons ◽  
Palladium Metal ◽  
Good Agreement

The direct and core-polarization contributions to the Knight shift in palladium metal have been calculated taking an enhancement factor of 10 for d- and 1.28 for s-electrons. We found a large negative contribution of - 3.88% for the core electrons and a comparatively small direct contribution of 0.18% for s-electrons on the Fermi surface. Together with an estimated contribution of 0.36% for conduction electrons in s-orbitals, but not on the Fermi surface, the calculated total amount of - 3.34% is in good agreement with the experimental value of - 4% obtained by the Jaccarino plot for palladium at 0 K

Effects of the isoscalar and isovector interaction on the ground-state magnetic moments of odd-mass 137–145Ce nuclei

2019 ◽  
Vol 97 (11) ◽  
pp. 1187-1190
Author(s):  
H. Yakut ◽  
E. Tabar ◽  
G. Hoşgör
Keyword(s):  
Ground State ◽  
Magnetic Moments ◽  
The Other ◽  
Spin Interaction ◽  
Nuclear Model ◽  
Isotopic Chain ◽  
Core Polarization ◽  
Polarization Effects ◽  
The Core

A systematic study of the magnetic properties of deformed odd-neutron 137–145Ce isotopes using the microscopic quasiparticle phonon nuclear model (QPNM) has been presented. The QPNM includes residual spin–spin interaction in both isoscalar and isovector channels. The analysis shows that in the isoscalar channel contributions to the magnetic moment coming from the neutron and proton systems practically cancel out each other. On the other hand, in the isovector channel, the coherent contribution coming from the quasiparticle–phonon interactions leads to a spin polarization (core polarization), which is important for determination of the quenched spin gyromagnetic factors (gs). The quenched spin gyromagnetic factors so called [Formula: see text] have been found to range from [Formula: see text] to [Formula: see text] in the odd-mass 137–145Ce isotopic chain, which is similar to its phenomenological value ([Formula: see text] between [Formula: see text] and [Formula: see text]). By taking into consideration the core polarization effects, the available experimental data are satisfactorily reproduced with an accuracy of 0.01μN–0.1μN.

Structure property relationships in core-shell BaTiO3–LiF ceramics

1993 ◽  
Vol 8 (4) ◽  
pp. 871-879 ◽  
Author(s):  
C.A. Randall ◽  
S.F. Wang ◽  
D. Laubscher ◽  
J.P. Dougherty ◽  
W. Huebner
Keyword(s):  
Experimental Data ◽  
Dielectric Properties ◽  
Dielectric Property ◽  
Potential Application ◽  
Microstructural Development ◽  
Core Shell ◽  
Structure Property ◽  
The Core ◽  
Structure Property Relationships ◽  
Multilayer Capacitors

A sintering, microstructural development and dielectric property study of BaTiO3–LiF ceramics was performed to assess the potential application of low-fired multilayer capacitors. Not only does LiF allow for sintering below 1000 °C, it also allows for the manipulation of dielectric properties and interfaces within BaTiO3–LiF ceramics. Using mixing laws, a model of the dielectric properties of the core-shell microstructures is presented that agrees well with the observed experimental data.

Dielectric properties of ferroelectric liquid crystals with lateral group in the core

2002 ◽  
Author(s):  
Alexej M. Bubnov ◽  
Milada Glogarova ◽  
Vera Hamplova ◽  
Miroslav Kaspar
Keyword(s):  
Liquid Crystals ◽  
Dielectric Properties ◽  
Ferroelectric Liquid Crystals ◽  
The Core ◽  
Lateral Group

Hyperfine structure of Eu I

1965 ◽  
Vol 289 (1416) ◽  
pp. 81-96 ◽  
Keyword(s):  
Theoretical Analysis ◽  
Hyperfine Structure ◽  
Relativistic Effects ◽  
Interaction Constant ◽  
Tensor Operator ◽  
Quadrupole Moments ◽  
Core Polarization ◽  
The Core ◽  
Least Squares Fit ◽  
Good Agreement

A theoretical analysis is made of the hyperfine structure of the twelve levels of Eu I 4 f 7 ( 8 S ) 6 s 6 p using intermediate-coupled eigenfunctions obtained from a least-squares fit of the energies of the levels. Relativistic effects for the 6 p electron are calculated throughout by tensor-operator techniques. Good agreement is obtained with the observed A values, treating as parameters the polarization of the core (by the f electrons) and the hyperfine interaction constant of the 6 s electron. The magnitude of the core polarization is related to data on Eu I 4 f 7 ( 8 S ) 6s 2 , Euii 4 f 7 ( 8 s ) 6 s , and Eu III 4 f 7 ( 8 S ). The hyperfine-structure anomalies also fall into a consistent pattern. The observed B values are related to quadrupole moments of 151 Eu and 153 Eu.

High Temperature NMR Study of 51V and 195Pt in the V3Pt Compound

1984 ◽  
Vol 39 (2) ◽  
pp. 145-147
Author(s):  
R. Rünger ◽  
D. Ploumbidis
Keyword(s):  
High Temperature ◽  
Temperature Dependence ◽  
Knight Shift ◽  
Core Polarization ◽  
Temperature Coefficients ◽  
Polarization Contribution ◽  
The Core ◽  
Nmr Study

Measurements of both the 51V and 195Pt Knight shift in the V3Pt compound are reported for temperatures ranging from 300 K to about 1300 K. The temperature coefficients of the Knight shift and the NMR linewidth have been determined. An interpretation of the observations is given in the frame of a model which is based on the temperature dependence of the core polarization contribution to the total Knight shift.

scholarly journals Dielectric Properties of Deep Ice Cores with Air-Hydrate Inclusions (Abstract)

1988 ◽  
Vol 10 ◽  
pp. 210
Author(s):  
Shinji Mae ◽  
Takeo Hondoh ◽  
Masayoshi Nakawo ◽  
C.C. Langway
Keyword(s):  
Activation Energy ◽  
Relaxation Time ◽  
Dielectric Properties ◽  
Time Variation ◽  
Volume Fraction ◽  
Ice Cores ◽  
Frequency Range ◽  
Temperature Range ◽  
The Core

Air-hydrate inclusions have been found in deep ice cores from Dye 3, Greenland, which were taken in August 1981. Although the concentration of the air-hydrate crystals decreased with time, when the core was stored at a temperature of −50 °C, they still existed to an appreciable extent in 1985. An ice specimen was cut out from the Dye 3 core at a depth of 1500 m, where the volume fraction of the hydrate crystals was about 10−3 by volume. Its dielectric properties were measured in September 1985, in a frequency range of 30-20 × 103 Hz and temperature range of −20° to −90°C. The activation energy obtained for the relaxation time of the Debye dispersion was about 0.2 eV, which is much smaller than that of pure ice. The measurement was repeated once a month for about a year, and the sample was stored at a temperature of −10 °C between measurements. The time variation of the dielectric properties has been discussed in relation to the deterioration of the air-hydrate crystals.

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