Borosulfate

 ( Borates ) 

The borosulfates are heteropoly anion compounds which have sulfate groups attached to boron atoms. Other possible terms are sulfatoborates or boron-sulfur oxides. The ratio of sulfate to borate reflects the degree of condensation. With B(SO₄)₄^5- there is no condensation, each ion stands alone. In B(SO₄)₃^3- the anions are linked into a chain, a chain of loops, or as B₂(SO₄)₆⁶⁻ in a cycle. Finally in B(SO₄)₂⁻ the sulfate and borate tetrahedra are all linked into a two or three-dimensional network. These arrangements of oxygen around boron and sulfur can have forms resembling silicates. The first borosulfate to be discovered was K₅B(SO₄)₄ in 2012 by the research group of Henning Höppe, although the compound class as such had been postulated already in 1962 by G. Schott and H. U. Kibbel. Over 80 unique compounds are known as of 2024.

They are distinct from the which have separate, uncondensed sulfate and borate ions.

Related compounds include boroselenates, borotellurates, and also boroantimonates, borogallates, borogermanates, borophosphates, boroselenites and borosilicates.

---

Formation Borosulfates are formed by heating Boron trioxide, oleum, or sulfuric acid, with metal carbonates. The degree of condensation is varied with the ratio of oleum to sulfuric acid. Pure oleum is more likely to yield compounds with disulfate groups.

---

Reactions When heated to around 500 °C the borosulfates decompose by emitting SO₃ vapour and form a metal sulfate and boric oxide.

---

List

boron sulfate		229.74	monoclinic	C2	a=7.7600, b=4.1664, c=8.6134; β=94.785°; Z=2	277.51	2.749	no cations; 3D mesh
			monoclinic	P2/ c	a=15.6974, b=11.436, c=8.5557; β=90.334°; Z=8			superacid
				P4/ ncc	a=9.1377, c=7.3423; Z=4
			monoclinic	P2/ c	a=15.697, b=11.4362, c=8.5557; β=90.334°
				Pc	a=7.635, b=9.342, c=8.432; β=92.55°			3D network, like tectosilicate
			orthorhombic	P212121	a=10.862, b=10.877, c=17.769
			orthorhombic	P21/ c	a=8.0191, b=10.2111, c=15.0401
			monoclinic	C2/ c	a=23.856, b=7.3507, c=12.3235; β=98.724(2)°; Z=8	2136.1	2.58	colourless
				P4/ ncc	a=9.1980, c=7.2458			decomposes at , proton conductor
			monoclinic	Cc	a=11.4403, b=14.9439, c=13.8693; β=93.662°
		271.38	monoclinic	C2	a=11.3685, b=6.5541, c=12.8328; β=106.247°; Z=4	918.0	1.964	SHG 1.1 × KDP; min PM wavelength 252 nm; decompose 300 °C
			monoclinic	P21/ c	a=7.7506, b=6.6685, c=24.355; β=92.562°; Z=4	1257.5	2.000	white
		343.12	orthorhombic	Ibca	a=7.2858, b=14.7048, c=22.7052; Z=8	2433.2	1.928	decomposes chains
			monoclinic	P2/ c	a=5.434, b=7.570, c=7.766; β=99.74°
			monoclinic	P21/ c	a=10.949, b=8.49, c=12.701; β=110.227°; Z=4
			orthorhombic	Pbca	a=11.6569, b=9.4094, c=17.4833; Z=8	1917.6	2.431	birefringence Δ n = 0.07 @ 589.3 nm
			orthorhombic	Pca21	a=10.730, b=13.891, c=18.197
			orthorhombic	P212121	a=8.624, b=9.275, c=16.671
								white
		711.22	trigonal	P	a=8.0165 c=7.4858 Z=1	416.62	2.835	colourless
		711.22	hexagonal	P	a = 13.9196, c = 7.4854, Z = 3	1253	2.821	colourless
		430.17	monoclinic	C2/ c	a=17.443, b=5.3145, c=14.2906; β=126.323°; Z=4	1067.3	2.677	phyllosilicate structure colourless decomposes
			monoclinic	P21/ n	a=7.9100, b=8.0815, c=9.0376; β=111.37°; Z=2	269.01	2.667	colourless decomposes
		706.94	triclinic	P	a=7.9609, b=7.9671, c=9.2343; α=64.959°, β=89.228°, γ=60.054°	444.96	2.638	200K
		706.94		R	a=7.9620, c=24.4231; Z=3	1340.84	2.627	room temperature
				P4/ ncc	a=8.9739 c=7.4114
			monoclinic	Cc	a=11.3368, b=14.66, c=13.6650; β=94.235°; Z=8
		313.50	monoclinic	C2	a=11.2631, b=6.4339, c=12.649;  β=105.707°; Z=4	882.4	2.360	colourless
pentapotassium borosulfate				P41	a=9.9023, c=16.1871	1687.2	2.471	first discovered
			orthorhombic	Ibca	a = 7.074, b = 14.266, c = 22.58
			monoclinic	I2/ a	a=14.524 b=7.3916 c=15.7857 β=115.50
			monoclinic	P21/ c	a=5.5188, b=15.1288, c=13.2660; β=92.88°			sheet
			monoclinic	P21/ n	a=8.0435, b=7.9174, c=9.3082; β=110.94° Z=2	553.63		colourless
		833.74	trigonal	P	a=8.1086, c=7.7509; Z=1	441.3	3.137	colourless
		833.74	trigonal	P	a=13.9196 c=7.4854
			monoclinic	C2/ c	a=17.4254, b=5.3397, c=14.3214; β=126.03°; Z=4	269.40	2.860	pink
			monoclinic	P21/ n	a=7.8892, b=8.1042, c= 9.0409; β=111.29°; Z=2	269.29	2.803	pink
		849.70	trigonal	P	a=7.991, c=7.669; Z=1	418.0	3.376	pink
		848.82	trigonal	P	a=7.9359 c=7.4398 Z=1	405.77	3.474	yellow
			triclinic	P	a=5.3096, b=7.0752, c=11.1977; α=81.154°, β=80.302°, γ=80.897°			cyclic
			triclinic	P	a=5.2470, b=7.1371, c=7.9222; α=73.814°, β=70.692°, γ=86.642°			chain
			monoclinic	P21/ n	a=8.0435, b=7.9174, c=9.3082; β=111.26°; Z=2	534.36		colourless
		875.46	trigonal	P	a=7.9971, c=7.4895; Z=1	414.81	3.505	colourless
		406.24	monoclinic	C2	a=11.3127, b=6.5152, c=12.971; β=105.411°; Z=4	921.6	2.928	colourless
			orthorhombic	Ibca	a=7.2759, b=14.794, c=22.637
			orthorhombic	Pnma	a=8.0415, b=10.647, c=20.425
			tetragonal	P43212	a=10.148, c=16.689; Z=4			band gap 3.99 eV
				P63/ m	a=6.502, c=19.02; Z=2
								white
		743.8	monoclinic	P21	a=7.5551, c=14.560, c=7.5517; β=90.2372°; Z=2			transparent
		743.8	tetragonal	I	a=7.6128, c=14.631; Z=2			at 500K
		493.48	orthorhombic	Pnma	a=12.574, b=12.421, c=7.319; Z=4	1143.1	2.867	decomposes
		573.54	monoclinic	P21/ n	a=7.470, b=15.334, c=12.220; β=93.29°; Z=4	1397.5	2.726
			orthorhombic	Pnma	a=1657.3, b=12.037, c=4.39484
		617.36	monoclinic	P21/ c	a=11.3309, b=7.1482, c=19.355; β=106.878°; Z=4	1500.1	2.73	colourless; Sr in 9 coordination by sulfate oxygens
			monoclinic	C2/ c	a=13.5172, b=11.3941, c=10.8994; β=93.447°			cyclic
			monoclinic	P21/ c	a=7.2686, b=12.7802, c=11.4930; β=101.343°; Z=2	1046.8	2.64	blue
			tetragonal	P41	a=13.8210, c=21.724; Z=8	4149.7	2.66	blue
			monoclinic	P21/ c	a = 6.7061 b = 16.0198 c = 8.1681 β = 94.923° Z = 2	874.27	2.55	red
	AgB(SO4)2			P4/ ncc	a=8.6679 c=7.2897
	AgB(S2O7)2		monoclinic	P21/ c	a = 9.507, b = 9.601, c = 11.730, β = 98.35° Z=4	1059.3	2.953	colourless
	CdB2(SO4)4
	CdB2O(SO4)3	438.20	orthorhombic	Pnma	a=8.9692 b=11.520 c=8.7275 Z=4	901.8	3.23	colourless
	Cd4B2O(SO4)6		trigonal	P	a=8.2222 c=7.9788 Z=1	467.14	3.78	colourless
	(I4)B(S2O7)22		triclinic	P	a = 11.3714 b = 11.5509 c = 12.7811 α = 68.638° β = 68.275° γ = 64.626° Z=2	1366.16	2.999	orange-brown
	Cs2B4SO10	501.12	monoclinic	C2	a=11.4012 b=6.5997 c=13.5702 β=103.934° Z=4	919.04	3.359	colourless
	Cs2B2O(SO4)3		monoclinic	P2/ c	a=14.765 b=6.710 c=12.528 β=104.50
	Cs3HB4S2O14			P63/ m	a = 6.5648, c = 19.5669 Z=2
	Cs3H2BOB(PO4)3		monoclinic	P21/ c	a=8.2436 b=6.7387 c=24.414 β=92.713° Z=4	1354.7	3.538	proton conductor
	CsB(SO4)(S2O7)		monoclinic	P21/ c	a=10.4525, b=11.319, c=8.2760; β=103.206; Z=4
	Cs3Li2B(SO4)4		monoclinic	P21/ n	a=13.7698 c=8.2376 c=13.9066 β=91.778
	Cs3Na2B(SO4)4		monoclinic	P21/c	a=13.6406 b=7.9475 c=13.9573 β=990.781
	CsK4B(SO4)4			P43212	a=9.9433 c=16.881
	BaB2(SO4)4		orthorhombic	Pnna	a = 12.791, b = 12.800, c = 7.317 Z = 4
	BaB2O(SO4)3		orthorhombic	Pnma	a=17.1848 b=12.3805 c=4.4226
	BaB(S2O7)22		monoclinic	I2/ a	a = 11.6077, b = 8.9144, c = 21.303, β = 104.034° Z = 4			chains
	La2B2(SO4)6		monoclinic	C2/ c	a=1379.2 b=1158.9 c=1139.5 β=93.611			cyclic
	Ce2B2(SO4)6		monoclinic	C2/ c	13.740 b=11.5371 c=11.3057 β=93.661			cyclic
	Pr2B2(SO4)6		monoclinic	C2/ c	a=13.711 b=11.5305 c=11.2643 β=93.668			cyclic
	Nd2B2(SO4)6		monoclinic	C2/ c	a=13.6775 b=11.51.34 11.2046 β=93.5909			cyclic
	Sm2B2(SO4)6		monoclinic	C2/ c	a=13.633 b=11.492 c=11.112 β=93.567			cyclic
	Eu2B2(SO4)6		monoclinic	C2/ c	a=13.602 b=11.470 c=11.050 β=93.465			cyclic
	Gd2B2(SO4)6		monoclinic	C2/ c	a=13.5697 b=11.4426 c=11.0271 β=			cyclic
	Tb2B2(SO4)6		monoclinic	C2/ c	a=13.5601 b=11.42.48 c=10.9881 β=93.534			cyclic
	Dy2B2(SO4)6		monoclinic	C2/ c	a=13.568 b=11.425 c=10.9703 β=93.540			cyclic
	Ho2B2(SO4)6		monoclinic	C2/ c	a=13.505 b=11.409 c=10.921 β=93.453			cyclic
	Er2B2(SO4)6		monoclinic	C2/ c	a=13.551 b=11.411 c=10.882 β=93.41			cyclic
	Tm2B2(SO4)6		monoclinic	C2/ c	a=13.4981 b=11.3617 10.8327 β=93.4500			cyclic
	Yb2B2(SO4)6		monoclinic	C2/ c	a=13.495 b=11.3452 c=10.7961 β=93.390			cyclic
	Lu2B2(SO4)6		monoclinic	C2/ c	a=13.469 b=11.364 c=10.799 β=93.369			cyclic
	Au3Cl4B(S2O7)2		monoclinic	P21/ c	a=10.6266 b=12.7938 c=12.7373 β=99.322° Z=4	1708.82	4.259	yellow
	Au2Cl4B(S2O7)2(SO3)		orthorhombic	Fddd	a=13.1467, b=17.8576 c=31.711 Z=16	7444.8	3.49	metallic grey or transparent green dependent on polarization
	PbB2(SO4)4	613.05	orthorhombic	Pnna	a=12.516 b=12.521 c=7.302 Z=4	114.43	3.558	loop chain
	PbB2O(SO4)3		orthorhombic	P21/ m	a=4.4000 b=12.1019 c=8.6043
	Bi2B2(SO4)6	659.08	orthorhombic	C2/ c	a = 13.568, b = 11.490, c = 11.106 Z=4	1728.8	3.894
	(H3O)BiB(SO4)24	1039.72		I	a=11.857, c=8.149 Z=2	1156.84	2.99	colourless; non-linear optical
	(UO2)B(SO4)2(SO3OH)	569.52	triclinic	P	a=5.448 b=7.021 c=13.522 α =92.248° β =95.347° γ =101.987° Z=2		3.762	green
	(UO2)2B2O(SO4)3(SO3OH)2	1058.23	monoclinic	P21/ n	a=10.872 b=11.383 c=14.812 β=92.481 Z=4		3.838	yellow

Categories: Borates, Sulfates

Post Comment