The borate fluorides or fluoroborates are compounds containing borate or complex borate ions along with fluoride ions that form salts with cations such as metals. They are in the broader category of mixed anion compounds. They are not to be confused with tetrafluoroborates (BF4) or the fluorooxoborates which have fluorine bonded to boron.

Examples formulanamemwsystemspace groupunit cell Åvolume Å3densitycommentreferencesBe2(BO3)(OH,F) · H2OBerboritetrigonalP3a = 4.434, c = 5.33490.82colourless Uniaxial (-) nω = 1.580 nε = 1.485

Max birefringence δ = 0.095γ-Be2BO3Fγ-BBF95.83 trigonalR32a=4.4418 c=19.909 Z=3340.171.946 Uniaxial (-) SHG 2.3 × KDP NH4Be2BO3F2ABBF132.87trigonalR32a=4.4398 c=12.4697 Z=3212.872.243 Uniaxial (-) no=1.49389 ne=1.41919 at 636 nmNaBe2BO3F2sodium beryllium borate fluoride (NBBF) C2a=12.643 b=8.729 c=7.591 β=113.6°768 double layers of borate rings sandwiching barium atoms. Between pairs of double layers are sodium ions with fluoride.Mg2(BO3)(F,OH)Pertsevite-(F)orthorhombicPna21a = 20.49, b = 4.571, c = 11.89 Z=161,113.6Density 3.12 transparent

Biaxial (+) nα = 1.609 nβ = 1.620 nγ = 1.642

2V: 65°

Max birefringence: δ = 0.033Mg3(BO3)(F,OH)3Fluoboritehexagonala = 8.8, c = 3.1208colourless Uniaxial (-) nω = 1.570 nε = 1.534

Max birefringence δ = 0.036Mg3(OH)[B(OH)4]2(SO4)FsulfoboriteorthorhombicPnmaa=10.132 b=12.537 c=7.775987.6Biaxial (-) nα = 1.527 nβ = 1.536 nγ = 1.551 2V 79°

Max birefringence δ = 0.024Na6Mg3B10O18F6monoclinicP21/ca=13.420 b=6.400 c=10.701 β=90.693°band gap 5.40 eV; birefringence Δn = 0.039 at 1064 nmNaMgBe2(BO3)2FNMBBFPc1a=4.5408 c=13.439birefringence 0.081 at 546.1 nmAl6(BO3)5F3JeremejevitehexagonalP63/ma = 8.5591, c = 8.1814519density 3.28

Uniaxial (-) nω = 1.653 nε = 1.640

Max birefringence δ = 0.013Al8(BO3)4(B2O5)F8704.7tetragonalP42/mmca=9.134 c=19.112 Z=41,595density 2.935 colourlessNa(Mg3)Al6(Si6O18)(BO3)3(OH)3FFluor-dravitetrigonalR3ma = 15.955, c = 7.153 Z=31,577density 3.120 dark brown

Uniaxial (-) nω = 1.645(2) nε = 1.621(2)

Max birefringence δ = 0.024Na(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3FFluor-elbaitetrigonalR3ma = 15.8933, c = 7.12221,558blue green Uniaxial (-)K6B12O19F4744.32orthorhombicPnmaa =15.291 b =7.707 c =8.672 Z=21022.02.419KBe2BO3F2 KBBFhexagonalR32a=4.427 c=18.744318.32.40Be2BO6F2 rings SHG 1.2 × KDP; UV cutoff 147 nmCa5(BO3)3FLi3CaB2O5F363.04orthorhombicPnmaa=25.685 b=3.4697 c=5.4404 Z=2484.842.487colourlessLi5Ca9(BO3)7F2P1NaCaBe2B2O6F KCaBe2B2O6F467.64P3_1ca=4.705 c=14.554 Z=2279.12.783Ca(Li2Al)Al6(Si6O18)(BO3)3(OH)3FFluor-liddicoatitetrigonalR3ma = 15.875, c = 7.126 Z=31,555density 3.02 Uniaxial (-) nω = 1.637 nε = 1.621

Max birefringence δ = 0.016CaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3FFluor-uvitetrigonalR3ma = 15.954, c = 7.214 Z=31,590black Uniaxial nω = 1.637 - 1.668 nε = 1.619 - 1.639

Max birefringence δ = 0.018 - 0.029KCaBe2B2O6F Sc2F2(B2O5)229.54orthorhombicPbama=9.667 b=14.199 c=4.0395 Z=4554.42.750colourlessK11Sc5(B5O10)4F6orthorhombicFdd2a 56.769 b 12.207 c 12.6088transparent to <190 nmNa(Mn2+)3Al6(Si6O18)(BO3)3(OH)3FFluor-tsilaisitetrigonalR3ma = 15.9398, c = 7.13631,570greenish yellow Uniaxial (-)NaFe3Al6Si6B3O30FNa(Fe2+3)Al6(Si6O18)(BO3)3(OH)3FFluor-schorltrigonalR3ma = 16.005, c = 7.176 Z=31,591.9black Uniaxial (-) nω = 1.660 - 1.661 nε = 1.636 - 1.637

Max birefringence δ = 0.024Na(Fe3+3)Al6(Si6O18)(BO3)3O3FFluor-buergeritetrigonalR3ma = 15.8692, c = 7.18821,568density 3.311 brown

Uniaxial (-) nω = 1.735 nε = 1.655

Birefringence 0.080Ca(Fe2+)3MgAl5(Si6O18)(BO3)3(OH)3FFluor-feruviteKCaZn2(BO3)2FLi6RbB2O6F263.73orthorhombicPnmaa=8.41 b=15.96 c=5.08 Z=26822.568RbBe2BO3F2RBBF TrigonalR32a=4.434 c=19.758 z=3 also contains BeO3F tetrahedra and BO3. It transmits radiation from 180 to 3500 nm.Rb18Mg6(B5O10)3(B7O14)2FmonoclinicC2/ca=11.06 b=19.70 c=31.01 β=90.13°RbCaBe2B2O6FTrigonalR32KSrBe2B2O6F LiSr3Be3B3O9F4NaSr3Be3B3O9F4K3Sr3Li2Al4B6O20FSHG 4 × KDP; 170 nm UV cutoffCa(Y,REE,Ca,Na,Mn)15Fe2+(P,Si)Si6B3O34F14Proshchenkoite-(Y)trigonalR3ma = 10.7527, c = 27.40022,743.6brownish(Y,REE,Ca,Na)15(Al,Fe3+)(CaxAs3+1−x)(Si,As5+)Si6B3(O,F)48Hundholmenite-(Y)trigonalR3ma = 10.675, c = 27.02 Z=32,667density 5.206 brownish

Uniaxial (-)(Na,Ca)3(Y,Ce)12Si6B2O27F14Okanoganite-(Y)trigonalR3ma = 10.7108, c = 27.0404.35Tan coloured Uniaxial (-) nω = 1.753 nε = 1.740

Max birefringence δ = 0.013? Y5(SiO4,BO4)3(O,OH,F)Tritomite-(Y)?hexagonala = 9.32, c = 6.843.05-3.4isotropic n = 1.627 - 1.685Cd8B5O15F1212.25cubicFdma = 13.972 Z = 82,7275.904colourlessCdZn2KB2O6FLi3Cs6Al2B14O28F1490.58orthorhombicPnmaa=21.8412 b=19.8875 c=7.1577 Z=43109.13.184CsBe2BO3F2247.74trigonalR32a=4.4575 c=21.310 Z=3366.73.366colourlessCs18Mg6(B5O10)3(B7O14)2FmonoclinicC2/ca=11.234 b=20.11 c=32.12 β=90.225°CsCaBe2B2O6FtrigonalR32BaBOF3 221.15monoclinicP21/ca = 4.620 b = 15.186 c = 4.426 β = 92.045° Z=4 310.3 contains chains of -OB(F2)- and a double chain of BaFBa5(BO3)3FLi2BaSc(BO3)2F332.80hexagonalP63/ma=4.895 c=14.346297.73.713LiBa12(BO3)7F4I4/mcmBaBe2BO3F3271.16hexagonalP63a=7.628 c=13.990 Z=6704.93.832UV cutoff <185 nm; birefringence 0,081 at 200 nmNaBa12(BO3)7F4I4/mcmBaMgBe2(BO3)2F2BMBBF335.283trigonalPc1a=4.5898 c=15.348280.013.976colourless [Be2B3O6F2]∞Ba3.75MgB7O14F2.5886.50monoclinicC2/ca 16.611 b 13.677 c 15.141 β 121.239° Z=82941.04.004transparent > 203 nm; birefringence 0.081@546 nmBaAl(BO3)F2hexagonalPa=4.8879 c=9.403 Z=2194.5UV cutoff 165 nmK3Ba3Li2Al4B6O20FK5Ba10(BO3)8FtrigonalRca = 15.293, c = 22.699 Z = 6KBa7Mg2B14O28F5monoclinicC2/ca = 16.638 b = 13.609 c = 15.214 β = 121.309° Z=42943.33.934colourlessBaCaBe2(BO3)2F2BCBBFtrigonalPc1a=4.6931 c=16.049306.123.808colourless [Be2B3O6F2]∞Li2BaSc(BO3)2FhexagonalP63/ma=4.895 c=14.346Ba3Zn(BO3)(B2O5)F656.82monoclinicP21/ca = 15.179 b = 7.0064 c = 8.763 β = 100.15° Z=4917.44.755colourlessBa4Zn2(BO3)2(B2O5)F2937.34monoclinicC2/ca=20.39 b=4.998 c=13.068 β = 192.59 Z=441,3314.679colourlessBaZnBe2(BO3)2F2376.35trigonalPa = 4.5998, c = 7.7037 Z = 1141.164.427colourlessRb3Ba3Li2Al4B6O20FBaCdBe2(BO3)2F2BDBBFPc1a=4.6808 c=15.788Ba1.09Pb0.91Be2(BO3)2F2BPBBFtrigonalPm1a = 4.7478 c = 8.386, Z = 1163.70UV absorption edge=279.1 nm; birefringence 0.054 at 546.1 nm; 2D [Be3B3O6F3]∞ layerLiBa2Pb(BO3)2ForthorhombicPmmna=5.487 b=15.96 c=4.034KNa3Na6Ca2Ba6Mn6(Ti4+,Nb)6B12Si36O114(O,OH,F)11TienshanitehexagonalP6/ma = 16.785, c = 10.454 Z=12,551pale olive green Uniaxial (-) nω = 1.666 nε = 1.653

Max birefringence δ = 0.013Ca6(Fe2+,Mn2+)Y3REE7(SiO4)3(PO4)(B3Si3O18)(BO3)F11Laptevite-(Ce)trigonalR3ma = 10.804, c = 27.726 Z=32,803density 4.61 dark brown

Uniaxial (-) nω = 1.741(3) nε = 1.720(3)

Max birefringence δ = 0.021Ba(Y,Ce)6Si3B6O24F2Cappelenite-(Y)trigonalP3a = 10.67, c = 4.68 Z=14614.407greenish brownCaMg[(Ce7Y3)Ca5](SiO4)4(Si2B3AsO18)(BO3)F11Arrheniusite-(Ce)trigonalR3ma = 10.8082, c = 27.5196Gd4(BO2)O5ForthorhombicPmmna=15.746 b=3.8142 c=6.609 Z=2396.96.45colourlessGd2(BO3)F3Gd3(BO3)2F3Gd4[B4O11]F2Ba2Gd(BO3)2ForthorhombicPnmaa = 7.571 b = 10.424 c = 8.581 Z = 2Eu5(BO3)3ForthorhombicPnmaa=7.225 b=14.124 c=9.859 Z=41006.16.306yellowTlBe2BO3F2TrigonalR32a=4.4387 c=19.942 Z=3340.274.673colourlessLiBa2Pb(BO3)2ForthorhombicPmmna=5.487 b=15.97 c=4.034353.45.887colourless(Ca,Ce,La,Th)15As5+(As3+0.5,Na0.5)Fe3+Si6B4O40F7Vicanite-(Ce)trigonalR3ma=10.881 c=27.332,7664.82greenish yellow Uniaxial (-) nω = 1.757 nε = 1.722

Max birefringence δ = 0.035

References