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Room-temperature measurements of the Buckingham effect (electric-field-gradient-induced birefringence, EFGIB) for gaseous oxygen are presented. The traceless electric quadrupole moment of the oxygen molecule has been deduced from ...
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Room-temperature measurements of the Buckingham effect (electric-field-gradient-induced birefringence, EFGIB) for gaseous oxygen are presented. The traceless electric quadrupole moment of the oxygen molecule has been deduced from these data, with the assumption that the temperatureindependent hyperpolarizability contribution to the EFGIB is negligibly small. The value obtained is Θ=(-1.033±0.027)×10~(-40) C m~2. This value is compared with the best available ab initio quantum computational values in the literature.
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This Table is a compilation of experimental measurements of static electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitati...
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This Table is a compilation of experimental measurements of static electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energy, half-life, spin and parity are given, along with a brief indication of the method and any reference standard used in the particular measurement. Experimental data from all quadrupole moment measurements actually provide a value of the product of the moment and the electric field gradient [EFG] acting at the nucleus. Knowledge of the EFG is thus necessary to extract the quadrupole moment. A single recommended moment value is given for each state, based, for each element, wherever possible, upon a standard reference moment for a nuclear state of that element studied in a situation in which the electric field gradient has been well calculated. For several elements one or more subsidiary EFG/moment reference is required and their use is specified.
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A new Table of Recommended Nuclear Electric Quadrupole Moments has been prepared and published by the Nuclear Data Section of the IAEA, Vienna Stone (2013). The main feature of the new Table is the adoption, wherever possible, of ...
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A new Table of Recommended Nuclear Electric Quadrupole Moments has been prepared and published by the Nuclear Data Section of the IAEA, Vienna Stone (2013). The main feature of the new Table is the adoption, wherever possible, of the best available calculation of the electric field gradient (efg), required to extract the moment from the measured quantity in most measurement methods. All original results have been normalized to take account of differences between the efg used in the original publication and the adopted value. The aim of the new table is to provide a standard reference in which the value given for each moment is the best available and for which full provenance is given.
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A P-ray detecting nuclear quadrupole resonance system has been developed at NSCL/MSU to measure ground-state electric quadrupole moments of short-lived nuclei produced as fast rare isotope beams. This system enables quick and sequ...
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A P-ray detecting nuclear quadrupole resonance system has been developed at NSCL/MSU to measure ground-state electric quadrupole moments of short-lived nuclei produced as fast rare isotope beams. This system enables quick and sequential application of multiple transition frequencies over a wide range. Fast switching between variable capacitors in resonance circuits ensures sufficient power delivery to the coil in the P-ray detecting nuclear magnetic resonance technique. The fast-switching technique enhances detection efficiency of resonance signals and is especially useful when the polarization and/or production rate of the nucleus of interest are small and when the nuclear spin is large.
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The most recent tabulations of nuclear magnetic dipole and electric quadrupole moments have been prepared and published by the Nuclear Data Section of the IAEA, Vienna [N. J. Stone, Report No. INDC(NDS)-0650 (2013); Report No. IND...
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The most recent tabulations of nuclear magnetic dipole and electric quadrupole moments have been prepared and published by the Nuclear Data Section of the IAEA, Vienna [N. J. Stone, Report No. INDC(NDS)-0650 (2013); Report No. INDC(NDS)-0658 (2014)]. The first of these is a table of recommended quadrupole moments for all isotopes in which all experimental results are made consistent with a limited number of adopted standards for each element; the second is a combined listing of all measurements of both moments. Both tables cover all isotopes and energy levels. In this paper, the considerations relevant to the preparation of both tables are described, together with observations as to the importance and (where appropriate) application of necessary corrections to achieve the "best" values. Some discussion of experimental methods is included with emphasis on their precision. The aim of the published quadrupole moment table is to provide a standard reference in which the value given for each moment is the best available and for which full provenance is given. A table of recommended magnetic dipole moments is in preparation, with the same objective in view. (C) 2015 AIP Publishing LLC.
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We report an extensive theoretical investigation of the electric moments and dipole (hyper)polarizability of xenon dihydride. We have employed conventional ab initio and DFT methods and large, flexible Gaussian-type basis sets. Ou...
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We report an extensive theoretical investigation of the electric moments and dipole (hyper)polarizability of xenon dihydride. We have employed conventional ab initio and DFT methods and large, flexible Gaussian-type basis sets. Our best values for the electric moments are obtained at the CCSD level of theory and are Θ = -4.8760 ea0~2 and Φ = -71.95 ea0~4. For the (hyper)polarizability, our best results, extracted from finite-field CCSD(T) calculations, are α = 49.93 and Δα = 55.80 e~2a0~2E_h~(-1), for the mean and the anisotropy of the dipole polarizability and γ = 31.26 x 10~3e~4a0~4E_h~(-3) for the mean second hyperpolarizability. Overall, the molecule is characterized by large (hyper) polarizability anisotropics. The DFT methods predict dipole polarizabilities comparable to those calculated by ab initio but overestimate the second hyperpolarizability.
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We report an extensive theoretical investigation of the electric moments and dipole (hyper)polarizability of xenon dihydride. We have employed conventional ab initio and DFT methods and large, flexible Gaussian-type basis sets. Ou...
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We report an extensive theoretical investigation of the electric moments and dipole (hyper)polarizability of xenon dihydride. We have employed conventional ab initio and DFT methods and large, flexible Gaussian-type basis sets. Our best values for the electric moments are obtained at the CCSD level of theory and are Θ = ?4.8760 ea 0 2 and Φ = ?71.95 ea 0 4 . For the (hyper)polarizability, our best results, extracted from finite-field CCSD(T) calculations, are $ \bar{\alpha } = 49.93 $ and ?α = 55.80 e 2 a 0 2 E h ?1 , for the mean and the anisotropy of the dipole polarizability and $ \bar{\gamma } = 31.26 \times 10^{3} e^{4} a_{0}^{4} E_{h}^{ - 3} $ for the mean second hyperpolarizability. Overall, the molecule is characterized by large (hyper)polarizability anisotropies. The DFT methods predict dipole polarizabilities comparable to those calculated by ab initio but overestimate the second hyperpolarizability.
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A survey of even-even nuclei in the nuclear chart showed regularities in the values of the ratio Q(2(1)(+))/root(B(E2) for each nucleus for which independent measurements of both the electric quadrupole moment of the 2(1)(+) state...
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A survey of even-even nuclei in the nuclear chart showed regularities in the values of the ratio Q(2(1)(+))/root(B(E2) for each nucleus for which independent measurements of both the electric quadrupole moment of the 2(1)(+) state, Q(2(1)(+)), and the reduced transition probability B (E2; 0(1)(+) -> 2(1)(+)) exist. As predicted by the rotational model, this ratio was found to be close to unity for the deformed nuclei in the rare-earth region. For non-rotational nuclei the absolute value of this ratio is almost always considerably lower. This latter observation can be interpreted within different models for different classes of nuclei as illustrated by a set of schematic IBA model calculations. A general mixing model and simple geometrical models are also suitable for collective non-rotational nuclei. Near magic nuclei a mechanism within the seniority scheme is compatible with the observed small value of R-QB. (C) 2018 Published by Elsevier B.V.
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We have carried out an accurate determination of the quadrupole moment of the deuteron nucleus. The evaluation of the constant is achieved by combining high accuracy Born-Oppenheimer calculations of the electric field gradient at ...
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We have carried out an accurate determination of the quadrupole moment of the deuteron nucleus. The evaluation of the constant is achieved by combining high accuracy Born-Oppenheimer calculations of the electric field gradient at the nucleus in the H2 molecule with spectroscopic measurements of the quadrupolar splitting in D_2 and HD. The derived value is Q = 0.285783(30) fm~2.
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This study provides a new determination of the nuclear electric quadrupole moment (NQM) for Xe-131, which is achieved by the molecular method. Dirac-Coulomb Coupled Cluster calculations with a Gaunt correction (DC+G-CC) of electri...
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This study provides a new determination of the nuclear electric quadrupole moment (NQM) for Xe-131, which is achieved by the molecular method. Dirac-Coulomb Coupled Cluster calculations with a Gaunt correction (DC+G-CC) of electric field gradients (EFGs) and experimental nuclear quadrupole coupling constants of six molecular systems (XeH+, XeCuF, XeCuCl, XeAgF, XeAgCl and XeAuF) were considered. The best NQM obtained by our DC+G-CCSD-T EFGs was -114.6(1.1) mbarn, which is recommended as the new reference value for this nuclide given the high level electron structure calculations done here. (C) 2016 Elsevier B.V. All rights reserved.
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