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Haas, H.

doi:10.1023/a:1020537714105

Cited by 8 publications

(6 citation statements)

References 9 publications

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“…The quadrupole frequency ʋ Q obtained from separation of the two satellites is rather small: ʋ Q = 174 kHz as indicated by the ticks in Fig. , which is consistent with experimental results of 180 kHz determined by Lue et al and theoretical calculations of Haas , which gives 170.6 kHz.…”

Section: Resultssupporting

confidence: 90%

NMR investigation of boron impurities in refined metallurgical grade silicon

Grafe

Löser

Schmitz

et al. 2015

Phys. Status Solidi A

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The nuclear magnetic resonance (NMR) method was applied for tracking boron impurities in the refining process of metallurgical grade (MG) silicon. From the NMR signal of the 11 B isotope at an operating temperature 4.2 K, the boron concentration can be estimated down to the order of 1-10 wppm B. After melting and resolidification of MG-Si alloyed with Ca and Ti, a major fraction of B impurities remains in the Si solid solution as inferred from the characteristic NMR frequency.

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Section: Resultssupporting

confidence: 90%

NMR investigation of boron impurities in refined metallurgical grade silicon

Grafe

Löser

Schmitz

et al. 2015

Phys. Status Solidi A

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“…[54] The average deviation from experiment reported in that study was 13 %, much smaller than the average 41 % deviation in our calculations. Plane-wave DFT EFG calculations that consider extended structures have been shown to provide accurate values of V ZZ for Sc [55,56] and Gd. [57] The calculated 139 La C Q value in LaBr 3 is much closer to experiment when the periodic nature of the salt is incorporated than the value calculated from an isolated fragment.…”

Section: Zora-dft Efg Calculations and Tensor Orientationsmentioning

confidence: 99%

An Investigation of Lanthanum Coordination Compounds by Using Solid‐State ¹³⁹La NMR Spectroscopy and Relativistic Density Functional Theory

Willans

Feindel

Ooms

et al. 2005

Chemistry A European J

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Lanthanum-139 NMR spectra of stationary samples of several solid La(III) coordination compounds have been obtained at applied magnetic fields of 11.75 and 17.60 T. The breadth and shape of the 139La NMR spectra of the central transition are dominated by the interaction between the 139La nuclear quadrupole moment and the electric field gradient (EFG) at that nucleus; however, the influence of chemical-shift anisotropy on the NMR spectra is non-negligible for the majority of the compounds investigated. Analysis of the experimental NMR spectra reveals that the 139La quadrupolar coupling constants (C(Q)) range from 10.0 to 35.6 MHz, the spans of the chemical-shift tensor (Omega) range from 50 to 260 ppm, and the isotropic chemical shifts (delta(iso)) range from -80 to 178 ppm. In general, there is a correlation between the magnitudes of C(Q) and Omega, and delta(iso) is shown to depend on the La coordination number. Magnetic-shielding tensors, calculated by using relativistic zeroth-order regular approximation density functional theory (ZORA-DFT) and incorporating scalar only or scalar plus spin-orbit relativistic effects, qualitatively reproduce the experimental chemical-shift tensors. In general, the inclusion of spin-orbit coupling yields results that are in better agreement with those from the experiment. The magnetic-shielding calculations and experimentally determined Euler angles can be used to predict the orientation of the chemical-shift and EFG tensors in the molecular frame. This study demonstrates that solid-state 139La NMR spectroscopy is a useful characterization method and can provide insight into the molecular structure of lanthanum coordination compounds.

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“…The electric field gradient at the regular boron site in MgB 2 of V zz = ͑+17.6± 0.8͒ V/Å 2 is large in comparison to other borides, 7 where V zz is typically smaller than 7 V / Å 2 . Since the lattice parameters are similar for these borides, this has to be attributed to the fact that the bonding in MgB 2 is based on p electrons only.…”

Section: Discussionmentioning

confidence: 85%

“…25 In this program the Bloch functions are constructed from atomcentered basis functions. In a recent study of the 7 Li EFG in Li x TiS 2 , 26 it was found that the size of the atomic basis sets has a strong effect on the quality of the calculated results. In particular d polarization functions at Li atoms were essential to reproduce experimental quadrupole coupling constants.…”

Section: Quantum Chemical Calculationsmentioning

confidence: 99%

See 1 more Smart Citation

Local electronic structure inMgB2fromB12
Indris
¹
,
Heitjans
²
,
Hattendorf³
et al. 2007
Phys. Rev. B

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We performed ␤-NMR spectroscopic studies on 12 B which was implanted into MgB 2 to get insight into the local electronic structure of this high-temperature superconducting material. By measuring electric field gradients we probed the electronic charge distribution anisotropy around boron in this solid and thus obtained experimental information about the bonding by p electrons. Besides the absolute value, the sign of the electric field gradient was also experimentally determined. By comparison with quantum chemical calculations, some of which were performed in the present work, and with results from conventional NMR spectroscopy on 11 B we were able to identify regular boron lattice sites as well as interstitial sites.

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Untitled

Cited by 8 publications

References 9 publications

NMR investigation of boron impurities in refined metallurgical grade silicon

NMR investigation of boron impurities in refined metallurgical grade silicon

An Investigation of Lanthanum Coordination Compounds by Using Solid‐State ¹³⁹La NMR Spectroscopy and Relativistic Density Functional Theory

Local electronic structure inMgB2fromB12
Indris
¹
,
Heitjans
²
,
Hattendorf³
et al. 2007
Phys. Rev. B

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Untitled

Cited by 8 publications

References 9 publications

NMR investigation of boron impurities in refined metallurgical grade silicon

NMR investigation of boron impurities in refined metallurgical grade silicon

An Investigation of Lanthanum Coordination Compounds by Using Solid‐State 139La NMR Spectroscopy and Relativistic Density Functional Theory

Local electronic structure inMgB2fromB12Indris1, Heitjans2, Hattendorf3 et al. 2007Phys. Rev. B

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An Investigation of Lanthanum Coordination Compounds by Using Solid‐State ¹³⁹La NMR Spectroscopy and Relativistic Density Functional Theory

Local electronic structure inMgB2fromB12
Indris
¹
,
Heitjans
²
,
Hattendorf³
et al. 2007
Phys. Rev. B