ChemInform Abstract: High‐Pressure Syntheses and Characterization of the Rare‐Earth Fluoride Borates RE₂(BO₃)F₃ (RE: Tb, Dy, Ho).

Abstract

High-Pressure Syntheses and Characterization of the Rare-Earth Fluoride Borates RE2(BO3)F3 (RE: Tb, Dy, Ho). -The new title compounds are prepared under high-pressure/high-temperature conditions from Ln2O3 (Ln: Tb, Dy, Ho), LnF3, and B2O3 (multianvil press, BN crucible, 900-1200°C, 1.5-3 GPa). The compounds are isotypic with Gd2(BO3)F3 (monoclinic, space group P21/c, Z = 8; single crystal XRD). The four crystallographically different Ln 3+ cations (coordination number of 9) are surrounded by O and F anions, B forms isolated trigonal-planar [BO3] 3groups, and the six crystallographically different Fare nearly planar coordinated by three Ln atoms. -(HINTEREGGER, E.; ENDERS, M.; PITSCHEIDER, A.; WURST, K.; HEYMANN, G.; HUPPERTZ*, H.; Z. Naturforsch., B: Chem. Sci. 68b (2013) 11, 1198-1206, http://dx.doi.org/10.5560/ZNB.2013-3258 ; Inst. Allg. Anorg. Theor. Chem., Leopold-Franzens-Univ., A-6020 Innsbruck, Austria; Eng.) -J. Schramke 06-018

Sc2F2(B2O5): a deep ultraviolet scandium borate fluoride exhibiting large birefringence induced by the synergistic effect of B2O5and ScOnF2groups

“…A series of rare-earth borate fluorides including LnB 2 O 4 F (Ln = La, Ce), RE 2 (BO 3 )F 3 (RE = La, Tb, Dy, Ho), RE 4 B 4 O 11 F 2 (RE = La, Pr, Nd, Sm, Eu, Ga, Tb, Dy, Ho, Er), Ln 3 (BO 3 ) 2 F 3 (Ln = Sm, Eu, and Gd), RE 5 (BO 3 ) 2 F 9 (RE = Dy, Er, Yb, Ho, Tm), Eu 5 (BO 3 ) 3 F, Gd 4 (BO 2 )O 5 F and Pr 4 B 3 O 10 F have been recorded. [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] These borate fluorides crystallize in centric space groups with BO 3 3− , B 2 O 5 4− , B 3 O 8 7− and B 4 O 11 10− groups building the anion framework. It is well known that the arrangement of anionic groups plays an important role in the optical anisotropy of a compound.…”