The rare-earth fluoride borates RE 4 B 4 O 11 F 2 (RE = Eu, Dy) were synthesized in a Walkertype multianvil apparatus from the corresponding rare-earth oxides and fluorides, and boron oxide. Eu 4 B 4 O 11 F 2 was obtained under high-pressure/high-temperature conditions of 5 GPa and 900 • C, and Dy 4 B 4 O 11 F 2 at 8 GPa and 1000 • C. The single-crystal structure determinations revealed that both compounds are isotypic to Gd 4 B 4 O 11 F 2 , crystallizing in the space group C2/c (Z = 4) with the parameters a = 1368.2(3), b = 465.4(1), c = 1376.6(3) pm, β = 91.2(1) • , V = 0.8765(3) nm 3 , R 1 = 0.0232, and wR 2 = 0.0539 (all data) for Eu 4 B 4 O 11 F 2 and a = 1349.5(3), b = 460.9(1), c = 1362.5(3) pm, β = 91.3(1) • , V = 0.8472(3) nm 3 , R 1 = 0.0353, and wR 2 = 0.0729 (all data) for Dy 4 B 4 O 11 F 2 . These phases are entirely different from the recently discovered lanthanum fluoride borate La 4 B 4 O 11 F 2 , which exhibits the same constitution in another structure type with space group P2 1 /c.

The rare earth fluoride borate Tm5(BO3)2F9 was synthesized from Tm2O3, B2O3, and TmF3 under high-pressure/high-temperature conditions of 5 GPa and 900 °C in a Walker-type multianvil apparatus. The single-crystal structure determination revealed that Tm5(BO3)2F9 is isotypic to the compounds RE5(BO3)2F9 (RE = Er,Yb). Tm5(BO3)2F9 crystallizes in the space group C2/c (Z = 4) with the parameters a = 2030.9(4), b = 606.2(2), c = 822.6(2) pm, β = 100.5(1)°, V = 995.7(3) Å3, R1 = 0.0341, and wR2 = 0.0724 (all data). The structure is composed of isolated BO3 groups, ninefold coordinated thulium cations, and fluoride anions. Infrared and Raman spectroscopic data of Tm5(BO3)2F9 are compared to the data of RE5(BO3)2F9 (RE = Er, Yb).

The new rare-earth fluoride borates RE 2 (BO 3 )F 3 (RE = Tb, Dy, Ho) were synthesized under highpressure/high-temperature conditions of 1.5 GPa/1200 • C for Tb 2 (BO 3 )F 3 and 3.0 GPa/900 • C for Dy 2 (BO 3 )F 3 and Ho 2 (BO 3 )F 3 in a Walker-type multianvil apparatus from the corresponding rareearth sesquioxides, rare-earth fluorides, and boron oxide. The single-crystal structure determinations revealed that the new compounds are isotypic to the known rare-earth fluoride borate Gd 2 (BO 3 )

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

Single crystals of the title compound are obtained from a stoichiometric mixture of B2O3, Tm2O3, and TmF3 (BN crucible, 5 GPa, 900 °C, 20 min).