Na3La9O3(BO3)8, a new oxyborate in the ternary system Na2-La2O3-B2O3 : preparation and crystal structure

Pierre Gravereau (1) , Jean-Pierre Chaminade (1) , Stanislav Pechev (1) , Velin Nikolov (2) , Diana Ivanova (2) , Pavel Peshev (2)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Institute of General and Inorganic Chemistry

A new oxyborate with a composition corresponding to the formula Na3La9O3(BO3)8 has been discovered in the ternary oxide system Na2O-La2O3-B2O3. Single crystals of this compound have been grown by spontaneous crystallization from melts of the constituent binary oxides during slow cooling. The structure of Na3La9O3(BO3)8 has been solved using X-ray data collected on a Nonius Kappa CCD diffractometer (Mo Kα radiation). The unit cell is hexagonal (space group P-62m, Z=1) with a=8.9033(3), c=8.7131(3) Å and V=598.14 Å3. Refinement of 49 parameters using 684 independent reflections with an intensity I>2σ(I) (Friedel not merged for absolute structure determination) results in R1=0.015 (wR2=0.030)...

Mots clés: Oxyborate of sodium and lanthanum; Crystal growth; Crystal structure

Domaines: Matériaux

Pierre Gravereau, Jean-Pierre Chaminade, Stanislav Pechev, Velin Nikolov, Diana Ivanova, et al.. Na3La9O3(BO3)8, a new oxyborate in the ternary system Na2-La2O3-B2O3 : preparation and crystal structure. Solid State Sciences, 2002, 4 (7), pp.993-998. ⟨10.1016/S1293-2558(02)01344-4⟩. ⟨hal-00717777⟩