of reference GaIV, GaV, and GaVI compounds by MAS and QPASS, extension of gallium/aluminum NMR parameter correlation

Toward a better description of gallo‐phosphate materials in solid‐state NMR: 1D and 2D correlation studies

“…1(a1), exhibits a unique resonance with a typical second-order quadrupolar lineshape. This signal can be well simulated using the isotropic chemical shift and quadrupolar interaction parameters (υ CS D 116 ppm, C Q D 4.7 MHz and Á Q D 0.45) in agreement with previously published data, 21 and confirming that gallium occupies a single tetrahedral site. The 31 P MAS NMR spectrum consists of a single resonance (υ CS D 8.9 ppm, FWHM D 155 Hz) corresponding also to a single crystallographic site.…”

Solid‐state NMR characterization of 69Ga and 71Ga in crystalline solids

“…Similar results have been observed by Massiot and coworkers in other gallium systems. 33 For virtually all the systems studied here, the oxygen atoms of the gallium polyhedra have been coordinated to other gallium atoms. However, as mentioned previously, the oxygen atoms in the gallium sulfate octahedra are coordinated to sulfur atoms.…”

Solid-state NMR Characterization of Six-coordinated Ga(III) Complexes with Sulfur-donor Ligands

“…Al for structurally analogous Ga and Al compounds in which only oxygen atoms occupy the first coordination sphere. 4 Considering that the reported 27 Al C Q value in tris(acetylacetonato)aluminum(III), Al(acac) 3 , is 3.03 MHz 5 and that CQ is proportional to the product of EFG and quadrupole moment, the estimated ratio of EFG values of Ga(acac)3 to Al(acac)3 was 2.7, which was close to the Massiot's scale factor.…”

“…On the other hand, the CT peaks in the 69 Ga MAS NMR spectra of the complexes other than Ga(S2CNMe2)3 did not exhibit the whole lineshape, although they were measured at a spinning rate of 28 kHz. To obtain NMR parameters such as the isotropic chemical shift (δiso), quadrupole coupling constant (CQ), and asymmetry parameter (η) in Table 1 Ga nuclei in the octahedral sites (GaO6) in MgGa2O4 (CQ = 7.6 MHz) and Y3Ga5O12 (CQ = 4.1 MHz), 4 and decreased in the following order, as listed in Table 1: Ga(S2CNEt2)3 > Ga(acac)3 > Ga (S 2 CNMe 2 ) 3 . The slightly smaller C Q value for the Ga (S 2 CNMe 2 ) 3 complex compared to that for the Ga(S2CNEt2)3 complex indicated that the electronic structure around the Ga nucleus in the former complex was less deviated from spherical symmetry than that in the latter complex.…”

“…4,7 The metal shielding in d 10 metal complexes with chalcogen-donor atoms tends to increase in the following order : O < S < Se. 8 Therefore, the Ga nuclei in Ga(S2CNMe2)3 and Ga(S2CNEt2)3 complexes were more shielded than those in the six-coordinate gallium compounds with oxygen-donor ligands and also than those in the fourcoordinate gallium compounds with sulfur-donor ligands such as γ-Ga2S3.…”