Oxalate fluoride

An oxalate fluoride is a mixed anion compound contains both oxalate and fluoride anions. Many of these compounds have high birefringence.

With nonmetals, some are related to the oxalatophosphates and oxalatoborates with the addition of fluoride.

Formation For some metal oxalate complexes, fluoride can displace some oxalate. This happens with aluminium.

With gallium the reverse happens, and oxalate displaces fluoride ligands.

Use Difluorooxalaotoborates are under investigation as electrolytes, or electrolyte additives in lithium ion batteries or supercapacitors. Their advantage is greater thermal stability, up to 200 or 300 °C, ability to form ionic liquids, and for supercapacitors, support for higher voltages (3 volts).

List formulanamecrystalspace groupcellvolumedensitycommentrefN(CH3)4BF2C2O4tetramethylammonium difluoro(oxalato)borateN(CH2CH3)4BF2C2O4tetraethylammonium difluoro(oxalato)boratetriethylmethylammonium difluoro(oxalato)boratemelt 15 °C; whiteN(-CH2CH2CH2CH2-)(CH2CH2CH3)(CH3)BF2C2O4N-Propyl-N-Methylpyrrolidinium Difluoro(oxalato)borate (Py13DFOB)melt 3.21 °CN(-CH2CH2CH2CH2-)(CH2CH2CH2CH3)(CH3)BF2C2O4N-butyl-N-methylpyrrolidinium difluoro(oxalato)borate (Py14DFOB)melt −5 °CN(-CH2CH2CH2CH2-)(CH2CH2CH2CH2CH3)(CH3)BF2C2O4N-pentyl-N-methylpyrrolidinium difluoro(oxalato)borate (Py15DFOB)glass transition −74 °CN(-CH2CH2CH2CH2-)(CH2CH2CH2CH2CH2CH3)(CH3)BF2C2O4N-hexyl-N-methylpyrrolidinium difluoro(oxalato)borate (Py16DFOB)melt 31 °C1-ethyl-1-methylpyrrolidinium difluoro(oxalato)boratemelt 10 °C; whiteN-ethoxyethyl-N-methylpiperidinium difluoro(oxalato)borate1-ethyl-3-methylimidazolium difluoro(oxalato)borate, [C2mim][DFOB]1-butyl-3-methylimidazolium difluoro(oxalato)borateN-ethoxyethyl-N-methylpiperidinium difluoro(oxalate)borateionic liquid, gl;ass transition -70 °CN-propyl-N-methylpiperidinium difluoro(oxalate)borateionic liquidLiBF2C2O4lithium difluoro(oxalato)borateorthorhombicCmcma = 6.2623 b = 11.437 c = 6.3002 Z = 4451.22LiBF2C2O4·2H2Olithium difluoro(oxalato)borate dihydratemonoclinicP21/ca = 9.5580 b = 12.7162 c = 5.4387 Z = 4634.63NaBF2C2O4sodium difluoro(oxalato)boratetetragonalI41mda=7.7316 c=8.5343510.16Na(C2BF2O4)(CH3CN)2orthorhombicPnmaa=11.6932 b = 14.1254 c = 6.5130 Z=41075.76B tertrahedral coordination by 2 F and twice by -OCCO-Na3Al(C2O4)2F2.3H2Osolubletriethylmethylphosphonium difluoro(oxalato)boratemelt 9 °C; whitediethylisobutylmethylphosphonium difluoro(oxalato)boratemelt 23 °C; whitetriisobutylmethylphosphonium difluoro(oxalato)boratetributylethylphosphonium difluoro(oxalato)boratelithium tetrafluoro(oxalato)phosphate (LiTFOP)Octahedral arrangement; P-OCCO- ringlithium difluorobis bis (oxalato) phosphate (LiDFBOP)Octahedral arrangement Two F trans on P; two oxalate diligands on equatorK3Al(C2O4)2F2.3H2Osoluble[NH4]2VO2F(C2O4)[N(CH3)4]2VO2F(C2O4)Na2VO2F(C2O4)K2VO2F(C2O4)[NH4][Cr(H2O)2F2(C2O4)]green[NH4]3[Cr(C2O4)2F2]·5H2Ogreen[NH4]3[Cr(C2O4)F4]·4H2OPyH[Cr(H2O)2F2(C2O4)] Py=pyridinegreenenH2[Cr(H2O)2F2(C2O4)]2. 2H2O en=ethylenediaminegreen[Cr(en)(H2O)2(C2O4)]2F. 2H2O en=ethylenediamine[Cr(en)2(C2O4)]2F. 2H2O en=ethylenediamineNa[Cr(H2O)2F2(C2O4)]. H2OgreenNa3[Cr(C2O4)2F2]·5H2OgreenNa3[Cr(C2O4)F4]·9H2OK[Cr(H2O)2F2(C2O4)]green; 2 water and two fluorides in cis positionK3[Cr(C2O4)2F2]·5H2OgreenK3[Cr(C2O4)F4]·3H2O[NH4][MnF(C2O4)]pale pink[NH4]2Mn(C2O4)F3pink; CAS 94138-08-6pyH[MnF2(C2O4)(H2O)2]monoclinicI2/aa = 7.2260 b = 15.2398 c = 9.916 β = 98.22° Z = 4Octahedral coordination on Mn, Cis-F opposite oxalate. 2 aqua is transNa[MnF(C2O4)]·2H2Opale pinkNa2Mn(C2O4)F3pink; CAS 94138-06-4Na2Mn2(C2O4)2.5F·2H2OtriclinicPa = 7.9129 b = 8.8497 c = 8.9252 α = 74.623o β = 72.361 o γ = 78.193 o, Z = 2birefringence 0.064@550 nm; light yellowK[MnF(C2O4)]pale pinkK2Mn(C2O4)F3pink; CAS 4138-07-5;Na2Fe(C2O4)F2monoclinicC12/c1a=15.8349 b=5.962 c=12.2784 β=111.968° Z=81075.02.816green[NH4]3[Fe(C2O4)2F2]·H2O[NH4][Fe(C2O4)F2]·3H2ONa[Fe(C2O4)F2]·2H2OFe(phen)3(BF4)(C2O4BF2)∙H2O phen = 1,10-phenanthrolinetris(1,10-phenanthroline)-iron tetrafluoroborate [ethanedioato](difluoro)borate monohydrateorthorhombicPca21a=10.816 b=16.929 c=19.491(imidH)2[Fe2(C2O4)F6]orthorhombicPbana=9.143 b=20.837 c=3.890 Z=2ladder, oxalate rungs[Fe2(C2O4)F4(DMSO)4]monoclinicP21/na=7.259 b=11.409 c=13.374 β=97.26° Z=2dimer, oxalate bridgedNa3[Fe(C2O4)2F2]·4H2Olight greenKFe(C2O4)ForthorhombicCmc21a=7.7633 b=11.8767 c=10.4206red or orangeK[Fe(C2O4)F2]·2H2Oyellowish greenK2[Fe(C2O4)2F]·3H2OK3[Fe(C2O4)2F2]·2.8H2Olight greenCo(NH3)6Al(C2O4)2F2.3H2Oorange yellow; insoluble[Co(NH3)6][Cr(C2O4)2F2]·6H2Opale green[Co(NH3)6][Cr(C2O4)F4]·4H2Opale green[Co(NH3)6][Cr(H2O)2F2(C2O4)]3. 2H2Oyellowish-green; sparingly soluble[Co(en)3][Cr(C2O4)2F2]·7H2Opale green[Co(en)3][Cr(C2O4)F4]·3H2Opale green[Co(en)3][Cr(H2O)2F2(C2O4)]3. 3H2Oyellowish green[Co(NH3)6][Fe(C2O4)F2]3·6H2Oorange yellow[Co(en)3][Fe(C2O4)F2]3orange yellow[Co(NH3)6]2[Fe(C2O4)2F]3·9H2Oorange yellow[Co(en)3]2[Fe(C2O4)2F]3·4H2Oorange yellow[Co(NH3)6][Ga(C2O4)2F2].3H2OinsolubleNi[Cr(H2O)2F2(C2O4)]2. 2H2OgreenNa2[GeF2(C2O4)2]·5.5H2OK2[GeF2(C2O4)2]·1.5H2OK2Ge(C2O4)2F2·2H2ORb2VO2F(C2O4)Rb2Ge(C2O4)2F2·2H2ORb2GeC2O4F4[YF(C2O4)(H2O)2]·2H2OK4Zr(C2O4)3F2·3H2OZr4O3F2(C2O4)4 · 2H2OK14Zr4 (C2O4)5F20·2H2ONa2ZrC2O4F4·2H2ONa2Zr2C2O4F8·4H2OK2ZrC2O4F4·2H2OKZr2(OH)3F2(C2O4)2 · 4H2OKZrF3C2O4KZrF3C2O4 · 3H2OK2ZrF4C2O4 K2ZrF4C2O4 · 2H2OK3Zr(C2O4)2F3· 3H2OK3ZrF5C2O4K4ZrF2(C2O4)3 ⋅ 2H2OK4Zr(C2O4)2CO3F2·5H2ORb2ZrC2O4F4·2H2ORb2Zr2C2O4F8·4H2ORb3Zr(C2O4)2F3· 3H2ONa3[NbO(C2O4)2F2]·3H2OK3[NbO(C2O4)2F2]·3H2OK3[Nb(C2O4)3F2]·5H2ORb3[NbO(C2O4)2F2]·3H2ORb4[Mo2O4 (C2O4)2F2]orthorhombica=1065 b=8.88 c=8.09 Z=23.52In(C2O4)F. 3H2ONH4[In(C2O4)F2].2H2ONa[In(C2O4)F2].2H2OK[In(C2O4)F2].3H2OK2[InF3(C2O4)H2O]monoclinicP21/ca=7.6943 b=9.8135 c=7.7252 β=109.648 Z=4549.353.300Rb2[InF3(C2O4)H2O]monoclinicP21/ca=7.8308 b=9.9671 c=7.9327 β=111.266 Z=4576.983.676[Co(NH3)6][In(C2O4)2F2].2H2O[Sn(C2O4)F-][NH4+]monoclinicP21/ca = 8.2736 b = 9.6386 c = 7.7473 β = 111.229° Z = 4NaSnC2O4F·H2OtriclinicPa = 5.9880 b = 7.2468 c = 8.2925 α = 111.020°β = 107.986° γ = 96.873° Z=2308.532.871birefringence 0.189 @ 532 nm; colourlessNa4Sn4(C2O4)3F6triclinicPa = 6.0283 b = 8.7916 c = 9.1191 α = 69.486 β = 81.508 γ = 83.017446.413.514birefringence 0.160 @532 nm; colourless; Na 5 or 6 coordinated; Sn type 1: coordinates 2 F and 2 O's from oxalate, which bridges to another Sn type 1) Type 2 Sn has one bond to F, two bonds to Os from an oxalate, and another O from another oxalate. Sn also has weak bonds to other SnKSn(C2O4)FmonoclinicP21/ca = 8.0692 b = 9.5398 c = 7.7245 β= 111.600° Z=4552.863.181colourlessK2[SnF2(C2O4)2] · 3H2OK2[SnF4(C2O4)] · 6.5H2OK2[Sn2F2(C2O4)6] · 2H2OK6[Sn2F4(C2O4)5] · 2H2ONH4Sb2(C2O4)F5birefringence 0.111 @546 nmNH4Sb(C2O4)F2·H2Obirefringence 0.381@546(NH4)4Sb2(C2O4)3F4·2H2OmonoclinicP21/na= 8.6392 b=9.8051 c=11.7908 β=94.628° Z=2995.522.308birefringence 0.066 @546(CN4H7)SbC2O4F2(H2O)0.5birefringence 0.126 @546 nmNa2Sb2(C2O4)F6birefringence 0.188 @546 nmKSb2C2O4F5monoclinicP21/ca=5.8691 b=6.5124 c=22.178 β=91.893° Z=4847.223.650birefringence 0.170 @532 nmK2Sb2(C2O4)F6birefringence 0.097 @546 nmRbSb2(C2O4)F5orthorhombicP212121 a=5.9822 b=6.5652 c=22.7919895.14SHG 1.3×KDP; birefringence 0.09 @546 nm[C(NH2)3]3Sb(C2O4)2F2·2H2OtriclinicPa=8.3223 b =11.0455 c=12.2379 α=69.660 β=76.132 γ=69.725 Z=2980.321.870birefringence 0.251@546nm[C(NH2)3]Sb(C2O4)F2·H2Obirefringence 0.323 @546 nmCs2Ge(C2O4)2F2·H2OCs2GeC2O4F4Cs2VO2F(C2O4)Cs2ZrC2O4F4·2H2OCs2Zr2C2O4F8·4H2OCs4[Mo2O4 (C2O4)2F2]orthorhombica=10.72 b=9.80 c=7.95 Z=23.98Cs2Sb2(C2O4)2F4∙H2Obirefringence 0.325@546Lanthanum fluorooxalate ??Neodymium fluorooxalate ??[TbrF(C2O4)(H2O)2]·2H2O?[DyF(C2O4)(H2O)2]·2H2ODysprosium fluorooxalateC2/ca=12.0047 b=11.0842 =8.2182 β=129.021°[HoF(C2O4)(H2O)2]·2H2OHolmium fluorooxalate[ErF(C2O4)(H2O)2]·2H2Oorthorhombica=11.217 b=13.046 c=9.191 Z=6[TmF(C2O4)(H2O)2]·2H2O[YBF(C2O4)(H2O)2]·2H2O[LuF(C2O4)(H2O)2]·2H2OK4Hf(C2O4)3F2·3H2OK14Hf4(C2O4)5F20·2H2OK3Hf(C2O4 2F3· 3H2ORb3Hf(C2O4 2F3· 3H2OK4Hf(C2O4)2CO3F2·5H2Owater soluble and stableH2[(C2O4)(OH)3Re·O·Re(OH)3F2]brown[NH4]2[(C2O4)(OH)3Re·O·Re(OH)3F2]brown[Co(NH3)6]2[(C2O4)(OH)3Re·O·Re(OH)3F2]3yellowish brown[Co en3]2[(C2O4)(OH)3Re·O·Re(OH)3F2]3yellowish brownK2[(C2O4)(OH)3Re·O·Re(OH)3F2]brownNi[(C2O4)(OH)3Re·O·Re(OH)3F2]brownBa[(C2O4)(OH)3Re·O·Re(OH)3F2]brownTl2[(C2O4)(OH)3Re·O·Re(OH)3F2]brown(UF2)C2O4 · 11/2H2O(UF)2(C2O4)3UF3(H2O)(C2O4)0.5monoclinicC2/ca = 17.246, b = 6.088 c = 8.589 β = 95.43° Z = 8Light green UIV tricapped trigonal prism coordination (9 fold); each U coordinates 6 bridging fluoride, one water, and two oxalates, which bridge to 3 other U atoms. One oxalate O is in the capped position, and the other 2 O are all on the common face.(H4TREN)[U2F6(C2O4)3]·4H2O (TREN = tris(2-aminoethyl)amine)monoclinicP21/ca = 19.1563, b = 8.9531 c = 16.6221 β = 114.633° Z = 42591.42.759green(H4APPIP)[U2F6(C2O4)3]·4H2O (APPIP = 1,4-bis(3-amino-propyl)piperazine)monoclinicP21/ca = 10.3309 b = 15.564 c = 17.537 β = 95.430° Z=42807.12.675greenNa3[UO2(C2O4)F3]⋅4H2OorthorhombicPnnma=7.9967 b=21.092 c=7.252 Z=41223.23.020yellowNa3[UO2(C2O4)F3]⋅6H2Otriclinicα°β°γ°K3[UO2(C2O4)F3]triclinicPa=9.682 b=10.274 c=10.612 α=104.008° β=97.041° γ=108.774° Z=4946.43.736yellowK3[UO2(C2O4)2F]⋅3H2OtriclinicPa=6.6530 b=9.105 c=12.120 α=96.372° β=90.714° γ=93.193° Z=2728.42.902Cs[UO2(C2O4)F]⋅H2OmonoclinicP21a=5.4954 b=16.226 c=9.6277 β=98.509° Z=4849.04.130yellowK2[UO2F2(C2O4)]triclinicPa=10.981 b=11.038 c=12.629 α=108.00° β=86.79° γ=123.99°1.31yellowK4[UO2F2(C2O4)2]triclinicPa=8.768 b=8.777 c=14.857 α=101.58° β=114.27° γ=85.27°4.16yellowK2[(UO2)2F4(C2O4)]monoclinica=10.792 b=12.028 c=10.615 β=136.88°2.92yellow; oxalate is tetradentate, bridging 2 URb2[UO2F2(C2O4)]yellowRb4[UO2F2(C2O4)2]yellowRb2[(UO2)2F4(C2O4)]yellow

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