Carbonate oxalate

The carbonate oxalates are mixed anion compounds that contain both carbonate (CO₃) and oxalate (C₂O₄) anions. Most compounds incorporate large trivalent metal ions, such as the rare earth elements. Some carbonate oxalate compounds of variable composition are formed by heating oxalates.^[1]

Formation

One method to form carbonate oxalates is to heat a metal salt with ascorbic acid, which decomposes to oxalate and carbonate and combines with the metal.^[2]

Reactions

When heated, oxalate carbonates decompose to carbon monoxide and carbonates, which form oxides at higher temperatures.^[2]

List

formula	name	formula weight	crystal form	space group	unit cell Å	volume Å3	density	properties	references
Sc									[3]
K4Ti2O2(C2O4)3·CO3									[4]
[Co*(C2O4)(CO3)]2−								anionic complex	[5]
[CoIII(CO3)(C2O4)(NH3)2]-								anionic complex	[6]
Sr[TiO(C2O4)CO3]									[7]
[Y(H2O)]2(C2O4)(CO3)2	yttrium oxalate carbonate	421.876	orthorhombic	C2221	a = 7.8177, b = 14.943, c = 9.4845, Z = 4	1108.0	2.526		[8]
Ba[ZrO(C2O4)(CO3)]									[9]
[Ce(H2O)]2[(C2O4)2(CO3)]·2.5H2O			triclinic	P1_	a 6.329 b 8.743 c 13.000, α 105.61° β 90.55° γ 105.10°				[10]
Pr4(C2O4)4(CO3)2]·3H2O	catena(bis(μ4-Oxalato)-(μ3-oxalato)-(μ2-oxalato)-bis(μ6-carbonato)-bis(μ2-aqua)-diaqua-tetra-praseodymium hydrate)		triclinic	P1_	a 6.298 b 8.673 c 12.970, α 105.42° β 90.55° γ 105.01°				[11]
Pr2(C2O4)(CO3)2									[12]
Nd4(C2O4)4(CO3)2]·3H2O	catena-[bis(μ4-Oxalato)-(μ3-oxalato)-(μ2-oxalato)-bis(μ6-carbonato)-bis(μ2-aqua)-diaqua-tetra-neodymium hydrate]		triclinic	P1_	a 6.273(6)Å b 8.616(7)Å c 12.928(9)Å, α 105.50(6)° β 90.52(7)° γ 105.00(6)°				[11]
(NH4)2[Nd2(CO3)(C2O4)3(H2O)]·H2O	diammonium aqua—carbonato-tri—oxalato-dineodymium(III) hydrate		triclinic	P1_	a=8.706 b=9.530 c=10.327 α = 73.35° β = 86.90° γ = 80.50° Z=2	809.69	2.808		[13]
Eu4(C2O4)4(CO3)2·3H2O	catena(bis(μ4-Oxalato)-(μ3-oxalato)-(μ2-oxalato)-bis(μ6-carbonato)-bis(μ2-aqua)-diaqua-tetra-europium hydrate)		triclinic	P1_	a 6.179 b 8.464 c 12.856, α 105.13° β 90.46° γ 104.86°				[11]
[Eu(H2O)]2(C2O4)(CO3)2									[14]
[Gd(H2O)]2(C2O4)(CO3)2									[14]
[Tb(H2O)]2(C2O4)(CO3)2									[14]
[Dy(H2O)]2(C2O4)(CO3)2									[14]
[Ho(H2O)]2(C2O4)(CO3)2									[14]
Er2(CO3)2(C2O4)(H2O)2			monoclinic	Cm	a = 7.773, b = 14.920, c = 4.7309, β = 90.12° Z = 2				[15]
Pb[ZrО(C2O4)CO3]
Pb4(CO3)2(C2O4)(OH)2		535.41	monoclinic	P21/c	a=11.8593 b=5.2486 c=9.0997 β =96.669 Z=4	562.58	6.321	colourless	[16]
(NH4)4[Th(CO3)2(C2O4)2]•0.5Н2O									[17]
(NH4)4[Th(CO3)2(C2O4)2]•10Н2O									[17]
(CN3H6)3(NH4)[Th(CO3)2(C2O4)2]•3Н2O									[17]
(CN3H6)3(NH4)[Th(CO3)3(C2O4)]•1.5Н2O									[17]
(CN3H6)3(NH4)[Th(CO3)3(C2O4)]•3Н2O									[17]
(CN3H6)6[Th2(CO3)5(C2O4)]	hexaguandinium pentacarbonatooxalato dithorium								[18]
(CN3H6)6[Th2(CO3)5(C2O4)2]•4Н2O									[17]
(CN3H6)6[Th2(CO3)5(C2O4)2]•8Н2O									[17]
(CN3H6)6[Th2(CO3)4(C2O4)3]•14Н2O									[17]
(CN3H6)8[Th2(CO3)7(C2O4)]									[17]
(CN3H6)8[Th2(CO3)7(C2O4)]•5Н2O									[17]
(CN3H6)8[Th2(CO3)7(C2O4)]•6Н2O									[17]
(CN3H6)8[Th2(CO3)5(C2O4)3]•Н2O									[17]
(CN3H6)10[Th2(CO3)8(C2O4)]•8Н2O									[17]
Na4[Th2(OH)2(CO3)4(C2O4)]•4Н2O									[17]
Na4[Th2(OH)6(CO3)2(C2O4)]•2Н2O									[17]
Na8Th(C2O4)2(CO3)4 •11Н2O									[19]
Na8[Th(CO3)5(C2O4)]•11Н2O									[17]
Na10[Th(CO3)5(C2O4)2]•11Н2O									[17]
Na10[Th(CO3)5(C2O4)2]•16Н2O									[17]
Na10[Th(OH)2(CO3)3(C2O4)3]•8Н2O									[17]
Na10[Th(OH)2(CO3)3(C2O4)3]									[17]
Na12[Th(CO3)6(C2O4)2]•11Н2O									[17]
K2[Th2(OH)2(CO3)3(C2O4)]•2Н2O									[17]
K2[Th2(OH)2(CO3)3(C2O4)]									[17]
K4[Th(CO3)3(C2O4)]•6Н2O									[17]
K5[Th2(OH)(CO3)4(C2O4)2]•2Н2O									[17]
K6[Th(CO3)4(C2O4)]•8Н2O									[17]
K6[Th(CO3)3(C2O4)2]•4Н2O									[17]
K6[Th2(CO3)5(C2O4)2]•2Н2O									[17]
K6[Th2(CO3)4(C2O4)3]•6Н2O									[17]
K8[Th2(CO3)5(C2O4)3]•13Н2O									[17]
K8[Th2(CO3)5(C2O4)3]•16Н2O									[17]
K10[Th2(CO3)7(C2O4)2]•8Н2O									[17]
K10[Th2(CO3)7(C2O4)2]•12Н2O									[17]
K10[Th2(CO3)7(C2O4)2]•14Н2O									[17]
K10[Th2(CO3)5(C2O4)4]•5Н2O									[17]
K10[Th2(CO3)5(C2O4)4]•7Н2O									[17]
(NH4)(CN3H6)3[(UO2)2(CO3)(C2O4)2(C3H4N2O2)] · H2O									[20]
(CN3H6)4[(UO2)2(CO3)(C2O4)2(C5H8N2O2)] · 1.5H2O	guanidonium μ-carbonate μ-ethylmethylgyoximatedioxylatediuranylate sesquihydrate		monoclinic	P21	a=6.909 b=15.794 c=30.064 β=96.720° Z=4	3258	2.383	red plates	[20][21]
(CN3H6)4[(UO2)2(CO3)(C2O4)2(C6H8N2O2)] · 3H2O									[20]
(NH4)(CN3H6)4[(UO2)2(CO3)(C2O4)2(C6H4N2O2)] · H2O									[20]
(CN3H6)4[(UO2)2(C6H8N2O2)(CO3)(C2O4)2] · (C6H10N2O2) · 2H2O	guanidinium (3-methyl-1,2-cyclopenadionedioxime)dioxalato (μ-3-methyl-1,2-cyclopenadionedioxato) μ-carbonatodiuranylate dihydrate		triclinic	P1_	a=9.2474 b=14.8562 c=16.8917 α = 68.504° β = 77.721° γ = 89.792° Z=2	2102.7	2.108	red	[22]
(CN3H6)4[(UO2)2(CO3)(C2O4)2(C7H10N2O2)] · H2O									[20]
NH4(CN3H6)3[(UO2)2(C7H10N2O2)(CO3)(C2O4)2] · 2H2O	ammonium guanidinium dioxalato (μ-3-methyl-1,2-cyclopenadionedioxato) μ-carbonatodiuranylate dihydrate		orthorhombic	P212121	a=9.904 b=17.400 c=18.757 Z=4	3232.2	2.393	red	[22]
(CN3H6)4[(UO2)2(CO3)(C2O4)2(C6H10N2O2)] · H2O	guanidinium dioxalato μ-diethylglyoximato μ-carbonatodiuranylate monohydrate	1176.59	monoclinic	P21/n	a=7.6140 b=15.4388 c=28.010 β=95.99° Z=4	3274.6	2.387	orange	[23]
(CN3H6)2(C2H2N2)[(UO2)2(CO3)(C2O4)2(C6H10N2O2)] · 3H2O	guanidinium ethylenediammonium dioxalato μ-diethylglyoximato μ-carbonatodiuranylate monohydrate							orange	[23]
[C(NH2)3]10[(UO2)6(μ3-O)2(μ2-OH)2(C2O4)4(CO3)4]· 2H2O		2913.21	triclinic	P1_	a=11.5919 b=11.7868 c=13.3545 α = 102.637° β = 93.278° γ = 95.273° Z=1	1759.7	2.749	yellow	[24]
Pu2(C2O4)2CO3	Plutonium(III) dioxalate monocarbonate								[25]
Pu2C2O4(CO3)2	Plutonium(III) monooxalate dicarbonate								[25]