Editing Thallium (section)

===Thallium(I)===
The [[thallium halides|thallium(I) halides]] are stable. In keeping with the large size of the Tl<sup>+</sup> cation, the chloride and bromide have the [[caesium chloride]] structure, while the fluoride and iodide have distorted [[sodium chloride]] structures. Like the analogous silver compounds, TlCl, TlBr, and TlI are [[photosensitive]] and display poor solubility in water.<ref name="Greenwood241">Greenwood and Earnshaw, p. 241</ref> The stability of thallium(I) compounds demonstrates its differences from the rest of the group: a stable [[thallium(I) oxide|oxide]], [[thallium(I) hydroxide|hydroxide]], and [[thallium(I) carbonate|carbonate]] are known, as are many chalcogenides.<ref name="Greenwood246">Greenwood and Earnshaw, pp. 246–247</ref>

The [[double salt]] {{chem|Tl|4|(OH)|2|CO|3|}} has been shown to have hydroxyl-centred triangles of thallium, {{chem|[Tl|3|(OH)]|2+}}, as a recurring motif throughout its solid structure.<ref>{{cite journal|title = Hydroxocentered {{chem|[(OH)Tl|3|]|2+}} triangle as a building unit in thallium compounds: synthesis and crystal structure of {{chem|Tl|4|(OH)|2|CO|3}}|first1 = Oleg I.|last1 = Siidra|first2 = Sergey N.|last2 = Britvin|first3 = Sergey V.|last3 = Krivovichev|journal = [[Z. Kristallogr.]]|volume = 224|issue = 12|pages = 563–567|doi = 10.1524/zkri.2009.1213|year = 2009|bibcode = 2009ZK....224..563S|s2cid = 97334707}}</ref>

The metalorganic compound thallium ethoxide (TlOEt, TlOC<sub>2</sub>H<sub>5</sub>) is a heavy liquid (ρ {{val|3.49|u=g·cm<sup>−3</sup>}}, m.p. −3&nbsp;°C),<ref>{{Cite book|title=Handbook of inorganic compounds|date=1995|publisher=CRC Press|others=Perry, Dale L., Phillips, Sidney L.|isbn=0-8493-8671-3|location=Boca Raton|oclc=32347397}}</ref> often used as a basic and soluble thallium source in organic and organometallic chemistry.<ref>{{Cite journal|last1=Frank|first1=Scott A.|last2=Chen|first2=Hou|last3=Kunz|first3=Roxanne K.|last4=Schnaderbeck|first4=Matthew J.|last5=Roush|first5=William R.|date=2000-08-01|title=Use of Thallium(I) Ethoxide in Suzuki Cross Coupling Reactions|journal=Organic Letters|volume=2|issue=17|pages=2691–2694|doi=10.1021/ol0062446|pmid=10990429|issn=1523-7060}}</ref>