Structure determination of β-Pb2ZnF6 by coupling multinuclear solid state NMR, powder XRD and ab initio calculations

C. Martineau (1, 2) , F. Fayon (3) , C. Legein (1) , J.Y. Buzaré (2) , M. Body (2) , D. Massiot (3) , F. Goutenoire (1)

1 LdOF - Laboratoire des oxydes et fluorures
2 LPEC - Laboratoire de physique de l'état condensé
3 CEMHTI - Conditions Extrêmes et Matériaux : Haute Température et Irradiation

The results from one-dimensional multinuclear (19F, 207Pb and 67Zn) magic-angle spinning nuclear magnetic resonance experiments combined with the use of the ISODISPLACE program allow for the space group determination of b-Pb2ZnF6 (no. 138 P42/ncm). The structure was refined from X-ray powder diffraction data (a = 5.633 (1)Å and c = 16.247 (1)Å , Z = 4). b-Pb2ZnF6 has one six-fold coordinated Zn, one eleven-fold coordinated Pb and five F non-equivalent crystallographic sites and is built from alternated layers parallel to the (a, b) plane; tilted ZnF42- layers of corner sharing ZnF64- octahedra and FPb+ layers of edge sharing FPb47+ tetrahedra. The structure of b-Pb2ZnF6 was then optimized using the ab initio code WIEN2k and the calculated 67Zn EFG is in agreement with the NMR results. 19F–19F proximities and 19F–207Pb connectivities were evidenced using through-space and through-bond NMR correlation experiments, respectively, and support the proposed structure.19F–207Pb J-coupling was also used to select fluorine resonances depending on the number of neighbouring lead ions, leading to an unambiguous assignment of the different 19F resonances.

Domaines: Matériaux; Cristallographie; Chimie inorganique

C. Martineau, F. Fayon, C. Legein, J.Y. Buzaré, M. Body, et al.. Structure determination of β-Pb2ZnF6 by coupling multinuclear solid state NMR, powder XRD and ab initio calculations. Dalton Transactions, 2008, 44, pp.6150-6158. ⟨10.1039/b810863c⟩. ⟨hal-00332543⟩