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Fig. la shows the spectrum obtained at 11.7 T

71Ga and 69Ga nuclear magnetic resonance study of β-Ga2O3: resolution of four- and six-fold coordinated Ga sites in static conditions

SOLID STATE NUCLEAR MAGNETIC RESONANCE, no. 4 (1995): 241-248

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摘要

Ga-71 and Ga-69 nuclear magnetic resonance (NMR) spectra have been obtained for beta-Ga2O3 at magnetic fields of 11.7 and 7.0 T with a combination of static and spinning samples and using echo techniques. Isotropic chemical shifts and well constrained electric field gradient (EFG) tensors were measured for the Ga-IV and Ga-VI sites in bet...更多

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简介
  • Solid-state gallium NMR is a growing subject of interest for physical chemistry and crystallography.
  • Most of the recently published work has been carried out at high magnetic fields under magic-angle spinning (MAS) with the aim of averaging second-order quadrupolar broadening.
  • 1O-29 m2, I = 3/2), for 6 Ga and ‘lGa the second-order quadrupole broadening of the < l/2 > transition is greater by a factor of N 11 (a~&) for a given EFG due to the spin (I) dependence of ho
重点内容
  • Solid-state gallium nuclear magnetic resonance (NMR) is a growing subject of interest for physical chemistry and crystallography
  • Fig. la shows the spectrum obtained at 11.7 T
  • Fourier transformation from the echo maximum ensures a flat baseline with all spinning sidebands in phase
  • Most of the features observed in the spectrum (trFaings.it.ilo.an>
  • Low-intensity, featureless parts of the spectrum are not reproduced with this single site simulation
  • It is likely that the Ga, contribution should lie underneath the Gav, resonance with a somewhat higher quadrupolar coupling but it is difficult or impossible to verify this with these acquisition conditions
结果
  • The spectrum extends over more than 200 kHz and is clearly far from the infinite spinning rate condition.
  • This explains the difficulties in interpreting spectra obtained using single-pulse excitation in addition to their associated dead time truncation problems.
  • It is likely that the Ga,, contribution should lie underneath the Gav, resonance with a somewhat higher quadrupolar coupling but it is difficult or impossible to verify this with these acquisition conditions.
  • Similar spectra have been obtained at 7.0 T spinning at lo-l.5 kHz leading to the same conclusions with even less resolution
结论
  • It is possible to obtain spectra of p-Ga,O, for both 69Ga and ‘lGa even at 7.0 T in which fourand six-fold sites are readily resolved.
  • This opens the way for further multi-isotopic investigations of gallium compounds and gallium-aluminium substitution by solid-state NMR even in the presence of high quadrupolar couplings [17]
总结
  • Introduction:

    Solid-state gallium NMR is a growing subject of interest for physical chemistry and crystallography.
  • Most of the recently published work has been carried out at high magnetic fields under magic-angle spinning (MAS) with the aim of averaging second-order quadrupolar broadening.
  • 1O-29 m2, I = 3/2), for 6 Ga and ‘lGa the second-order quadrupole broadening of the < l/2 > transition is greater by a factor of N 11 (a~&) for a given EFG due to the spin (I) dependence of ho
  • Results:

    The spectrum extends over more than 200 kHz and is clearly far from the infinite spinning rate condition.
  • This explains the difficulties in interpreting spectra obtained using single-pulse excitation in addition to their associated dead time truncation problems.
  • It is likely that the Ga,, contribution should lie underneath the Gav, resonance with a somewhat higher quadrupolar coupling but it is difficult or impossible to verify this with these acquisition conditions.
  • Similar spectra have been obtained at 7.0 T spinning at lo-l.5 kHz leading to the same conclusions with even less resolution
  • Conclusion:

    It is possible to obtain spectra of p-Ga,O, for both 69Ga and ‘lGa even at 7.0 T in which fourand six-fold sites are readily resolved.
  • This opens the way for further multi-isotopic investigations of gallium compounds and gallium-aluminium substitution by solid-state NMR even in the presence of high quadrupolar couplings [17]
表格
  • Table1: Acquisition
  • Table2: P-Ga,O,
Download tables as Excel
基金
  • Grandinetti for helpful discussions, Region Centre, Centre National de la Recherche Scientifique and Ecole Superieure de Physique et de Chimie Industrielle de la Ville de Paris (ESPCI) for financial support and technical assistance, respectively
引用论文
  • [l] H.K.C. Timken and E. Oldfield, J. Am. Chem. Sot., 109 (1987) 7669-7673.
    Google ScholarLocate open access versionFindings
  • J. Zhong and P.J. Bray, J. Non-Cryst. Solids, 94 (1987) 122-132.
    Google ScholarLocate open access versionFindings
  • S.A. Axon, K. Huddersman and J. Klinowski, @em. Phys. Lett., 172 (1990) 398-404.
    Google ScholarLocate open access versionFindings
  • CR. Bayense, A.P.M. Kentgens, J.W. de Haan, L.J.M. van de Ven and J.H.C. van Hoff, J. Phys. C/rem., 96 (1992) 775-782. [S] E. Aubay and D. Gourier, Phys. Reu. B, 47 (1993)
    Google ScholarLocate open access versionFindings
  • [7] S. Geller, J. Chem. Phys., 33 (1960) 676-684. Taulelle, Magn. Reson. Chem., 28 (1990) S82-S88.
    Google ScholarLocate open access versionFindings
  • [9] D. Massiot, C. Bessada, J.P. Coutures and F. Taulelle, J. Magn. Reson., 90 (1990) 231-242.
    Google ScholarLocate open access versionFindings
  • [lo] D. Massiot, B. CotB, F. Taulelle and J.P. Coutures, in P. Colombet (Ed.), Application of NMR to Cement Science, Gordon and Breach, 1994.
    Google ScholarLocate open access versionFindings
  • Werner, M.A. Eastman and A. Pines,.I. Magn. Reson. A, 103 (1993) 72-81.
    Google ScholarLocate open access versionFindings
  • [12] P. Granger, Magn. Reson. Chem., 28 (1990) 156-158.
    Google ScholarLocate open access versionFindings
  • [13] G. Engelhardt and H. Keller, Magn. Reson. C/rem., 29 (1991) 941-945.
    Google ScholarLocate open access versionFindings
  • [14] K. Narita, J.I. Umeda and H. Kusumoto, J. C/rem. Phys., 44 (1966) 2719-2723.
    Google ScholarLocate open access versionFindings
  • [15] S.M. Bradley, R.F. Howe and R.A. Kydd, Magn. Reson. Chem., 31 (1993) 883-886.
    Google ScholarLocate open access versionFindings
  • [16] F. Taulelle, J. Maquet, V. Lucas, J. Thery, A. KhanHarari, T. Faltens and B. Dunn, Applied Magn. Reson., 4 (1992) 101-120.
    Google ScholarLocate open access versionFindings
  • [17] N. Gautier, I. Farnan, D. Massiot and J.P. Coutures, 12th European Experimental NMR Conference, Oulu, June S-10, 1994.
    Google ScholarFindings
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