Borotellurate Explained

The borotellurates are heteropoly anion compounds which have tellurate groups attached to boron atoms. The ratio of tellurate to borate reflects the degree of condensation. In [TeO<sub>4</sub>(BO<sub>3</sub>)<sub>2</sub>]8- the anions are linked into a chain. In [TeO<sub>2</sub>(BO<sub>3</sub>)<sub>4</sub>]10− the structure is zero dimensional with isolated anions. These arrangements of oxygen around boron and tellurium can have forms resembling silicates. The first borotellurates to be discovered were the mixed sodium rare earth compounds in 2015.

The tellurate is of the form TeO6 in an octahedral arrangement. The borate is in the form BO3, with two oxygen atoms shared with two tellurate TeO6 groups.

Related compounds include boroantimonates, galloborates, borogermanates, borophosphates, boroselenates, boroselenites, and borosulfates.[1]

Formation

Borotellurates are formed by heating boric acid, and tellurium dioxide, with metal carbonates or oxides at over 800 °C. Lower temperatures can be used with a flux like potassium carbonate.

Reactions

When heated to around 800 °C the borotellurates decompose by emitting TeO3 vapour and form a metal borate or metal tellurite.[2]

List

chemmwcrystal systemspace groupunit cell Åvolumedensitycommentreferences
Rb3BaTeB7O15837.02monoclinicP21/na=9.102 b=6.409 c=25.794 β=97.278 Z=41492.63.725actually this is a tellurite[3]
Sr5TeO2(BO3)4832.94tetragonalP4/mnca= 7.6005 c=10.401 Z=2600.824.604colourless; birefringence is 0.048 at 1064 nm[4]
Na2Y2TeO4(BO3)2533.02monoclinicP21/ca=6.3073, b=9.9279, c=6.7219; β=104.26°; Z=2407.944.339[5]
barium tellurium borateBa4B8TeO191067.44monoclinicCca=11.512 b=6.667 c=19.700 β=105.734 Z=41455.34.872double layers; SHG 1×KH2PO4[6]
Ba2Mg2TeB2O10632.52orthorhombicCmcaa=6.177 b=10.383 c=12.956 Z=4830.95[7]
Na2Dy2TeO4(BO3)2680.20monoclinicP21/ca=6.3089, b=9.9808, c=6.7489; β=104.394°; Z=2411.625.488decompose 842.1
Na2Ho2TeO4(BO3)2685.06monoclinicP21/ca=6.3060, b=9.9360, c=6.7339; β=104.230°; Z=2408.985.563decompose 844.2
Na2Er2TeO4(BO3)2689.72monoclinicP21/ca=6.2964, b=9.9056, c=6.7089; β=104.110°; Z=2405.815.645decompose 850.5
Na2Tm2TeO4(BO3)2693.06monoclinicP21/ca=6.2801, b=9.8594, c=6.6918; β=104.010°; Z=2401.895.727decompose 852.0
Na2Yb2TeO4(BO3)2701.28monoclinicP21/ca=6.2631, b=9.8269, c=6.6741; β=103.972°; Z=2398.625.843decompose 871.0
Na2Lu2TeO4(BO3)2705.14monoclinicP21/ca=6.2588, b=9.7998, c=6.6539; β=103.714°; Z=2396.485.907decompose 878.5
Pb2Mg2TeB2O10772.22orthorhombicCmcaa=6.055 b=10.300 c=12.521 Z=4780.97

Notes and References

  1. Kong . Fang . Ma . Yunxiang . Mao . Jianggao . Lanthanide Inorganic Solids Based on Main Group Borates and Oxyanions of Lone Pair Cations: Lanthanide Inorganic Solids Based on Main Group Borates and Oxyanions of Lone Pair Cations . Chinese Journal of Chemistry . January 2018 . 36 . 1 . 63–72 . 10.1002/cjoc.201700597.
  2. Daub. Michael. Krummer. Michael. Hoffmann. Anke. Bayarjargal. Lkhamsuren. Hillebrecht. Harald. 2017-01-26. Synthesis, Crystal Structure, and Properties of Bi 3 TeBO 9 or Bi 3 (TeO 6)(BO 3): A Non-Centrosymmetric Borate-Tellurate(VI) of Bismuth. Chemistry - A European Journal. en. 23. 6. 1331–1337. 10.1002/chem.201602480. 27981647.
  3. Sun. Jun. Mutailipu. Miriding. Cheng. Shichao. Yang. Zhihua. Pan. Shilie. 2020. Rb 3 BaTeB 7 O 15 : a novel [B 7 O 16 ] fundamental building block in a new telluroborate with [TeO 3 ] polyhedra]. Dalton Transactions. en. 49. 26. 8911–8917. 10.1039/D0DT01102A. 32555807. 219910405. 1477-9226.
  4. Tang. Ruling. Hu. Chunli. Feng. Jianghe. Fang. Zhi. Chen. Yan. Kong. Fang. Mao. Jianggao. 2020. Sr 5 TeO 2 (BO 3) 4 and NaSr 5 (BO 3)(SiO 4) 2 : two inorganic metal borate derivatives with diverse zero dimensional anions. Dalton Transactions. en. 49. 12. 3743–3749. 10.1039/C9DT03839F. 31729509. 208037429. 1477-9226. subscription.
  5. Feng . Jiang-He . Hu . Chun-Li . Xu . Xiang . Kong . Fang . Mao . Jiang-Gao . Na 2 RE 2 TeO 4 (BO 3) 2 (RE = Y, Dy–Lu): Luminescent and Structural Studies on a Series of Mixed Metal Borotellurates . Inorganic Chemistry . 2 March 2015 . 54 . 5 . 2447–2454 . 10.1021/ic503068s. 25692324 .
  6. Liu. Lili. Young. Joshua. Smeu. Manuel. Halasyamani. P. Shiv. 2018-04-16. Ba 4 B 8 TeO 19 : A UV Nonlinear Optical Material. Inorganic Chemistry. en. 57. 8. 4771–4776. 10.1021/acs.inorgchem.8b00510. 29613780. 0020-1669. subscription.
  7. Wen. Ming. Wu. Hongping. Hu. Cong. Yang. Zhihua. Pan. Shilie. 2019-08-19. Experiment and First-Principles Calculations of A 2 Mg 2 TeB 2 O 10 (A = Pb, Ba): Influences of the Cosubstitution on the Structure Transformation and Optical Properties. Inorganic Chemistry. en. 58. 16. 11127–11132. 10.1021/acs.inorgchem.9b01693. 31355637. 198965987. 0020-1669. subscription.