α-Gallium oxide deuteriohydroxide: a powder neutron diffraction investigation

Abstract

Les distances baryum-oxyg~ne sont donn~es dans le m~me tableau. C'est fi notre connaissance le premier anion de ce type signal~ dans le domaine de la cristallochimie des arsbniates.I1 est probable que la formulation chimique correcte de ce sel est Ba(OH)6As40 s. Une &ude est en cours pour tenter de localiser les protons dans cet arrangement.

Structural evolution in Pt/Ga-Zn-oxynitride catalysts for photocatalytic reforming of methanol

“…However, the XRD pattern changed drastically if the Pt precursor was calcined in air (see line a in Figure 3). Beside the wurtzite-type structure, significant amount of a new phase appeared, which could be identified as α-GaOOH (# 87-1901) [48,49]. The XPS characteristics of selected reduced or calcined Ga-Zn-oxynitrides (Supplementary Material section S2, Table S2) were essentially undistinguishable from those of the as synthesized materials, confirming that neither reduction nor calcination altered even the surface of the photocatalysts if they were free of Pt.…”

Gallium(III) adsorption on carbonates and oxides: X-ray absorption fine structure spectroscopy study and surface complexation modeling

“…Such first-shell splitting is similar to that observed in Ga oxyhydroxides (e.g., α-GaOOH), where the difference between Ga-O and Ga-OH bond lengths (1.93 and 2.08 Å, respectively, Ref. [36]) induces signifi- Table 1 Structural parameters of the atomic environment of gallium adsorbed on mineral surfaces at ambient temperature and pressure from 0.01 M NaNO 3 solution, Note. R = gallium-backscatterer mean distance, N = backscatterer coordination number, σ 2 = squared Debye-Waller factor (relative to σ 2 = 0 adopted in the calculation of reference amplitude and phase functions by FEFF8); E = nonstructural parameter accounting for phase shift of total EXAFS spectrum between experiment and FEEF calculation; R-factor defines goodness of the total fit in R-space as described in IFEFFIT [29]; (f) = DW factor was varied in initial fits and then fixed at the best value in the final fit.…”

X-ray absorption and Raman characterizations of TeO2–Ga2O3 glasses

“…The vðkÞ filtered EXAFS oscillations of the glasses, Fig. 10, are compared with those of crystalline compounds taken as references, b-Ga 2 O 3 , GaPO 4 and GaOOH (GaO 6 sites, R mean ¼ 2 A [36]). The vðkÞ EXAFS oscillations of the glasses present close similitude with those obtained for the reference b-Ga 2 O 3 containing equal proportion of GaO 4 and GaO 6 sites.…”