Talk:Tellurium monoxide

Tellurium monoxide- is it a compound or a mixture in the solid state

The evidence in the article for the existence of solid TeO is mainly very old. The atomistry reference (ref 5) does include the (unreferenced) statement "According to Damiens, however, the substance obtained is a mixture of tellurium and tellurium dioxide" The Encyclopedia of Inorganic chemistry, R Bruce King Editor,1994, states that TeO only exists as a gas phase entity formed when heating TeO₂. There appears to be no evidence for a phase TeO see this ref, The O-Te (oxygen-tellurium) system, V. P. Itkin, C. B. Alcock, Journal of Phase Equilibria 04/1996; 17(6):533-538. DOI:10.1007/BF02666000. See also Laser recording in tellurium suboxide thin films, Y.‐S. Tyan, D. R. Preuss, F. Vazan, and S. J. Marino, J. Appl. Phys. 59, 716 (1986);doi.org/10.1063/1.336588 where they found that the phase TeO_x the so called suboxide consisted of TeO₂ with Te "granules". This description of the suboxide film produced on DVDs is mentioned in the article but is not given the prominence it deserves. Reputable university level text books have the following, Greenwood and Earnshaw say TeO exists in flames and Hollemann & Wiberg do not mention it. I think this article needs a substantial rewrite to highlight the lack of modern evidence for the solid state compound, include the evidence for the TeO₂ / Te mixture in thin films ( misleadingly called tellurium suboxide) but include a mention of the gas phase diatomic molecule.Axiosaurus (talk) 10:22, 12 April 2013 (UTC)

What is TeO?

Step 1 would be to define the structure of TeO focusing on secondary sources per WP:SECONDARY. --Smokefoot (talk) 12:16, 7 May 2013 (UTC)

It already mentions the possible structures that TeO can take on and they all are sourced. ^King Jakob _C2 15:37, 7 May 2013 (UTC)

To prove a solid exist as a well defined compound X-ray crystallography can be used to tell if the crystal structure is unique or is just Te and TeO2 mixed as fine crystals. Has anyone done this? Also the reactions mentioned, are they being done with the "solid" or gas? Lastly there is a reference that is a google search. This should actually point to one of the results that support the statement, not leave it up to the reader to check what the search results are, particularly looking to see if something is not there. Google is not perfect or itself counted as a reliable source. Graeme Bartlett (talk) 21:05, 7 May 2013 (UTC)

• King jakob: To try and clarify Smokefoot's point (If I may). The page does say that it's a black solid, but this doesn't tell us anything about it's chemical structure. The structure is important, as it has a big effect on the chemistry. The page also gives 2 different formulas (TeO and Te₂O₂), which surely warrants some clarification. Is Te₂O₂ made of two TeO's joined together or is it arranged differently somehow? I'm afraid the references provided don't really answer these questions.

The only secondary source I can locate is here. It would support TeO, which has a CAS number of 13451-17-7. Tellurium suboxide seems to refer to a non-stoichiometric compound, TeO_x, which would appear to be the form used in CD's and DVD's, example here. Te₂O₂ I can find virtually nothing on, I think it's just an exotic gas-phase dimmer but I may be wrong on this. There's not much to go on and it only ever seems to be mentioned in passing. Project Osprey (talk) 22:53, 7 May 2013 (UTC)

This source says "Tellurium monoxide or tellurium suboxide, TeO, is...", which is why I use sources discussing both TeO and tellurium suboxide in the article. ^King Jakob _C2 23:00, 7 May 2013 (UTC)

• I did read the sources, but if you search the literature for tellurium suboxide most of it refers to TeO_x. Perhaps the usage has changed slightly over the years, the book is from 1931. Project Osprey (talk) 23:12, 7 May 2013 (UTC)

TeO crystal would be chemically unusual to me. Perhaps it is a non-stiochiometric Te₄O₉ (doi:10.1107/S0567740875005018), Te₂O₅ (doi:10.1107/S0567740873003092) or TeO₂, or their mixture (with oxygen or/and Te vacancies). Materialscientist (talk) 01:45, 8 May 2013 (UTC)

• @Project Ospery, tellurium oxide appears to be TeO_x such that x is less than 2, which allows for it to include TeO.^King Jakob _C2 18:43, 10 May 2013 (UTC)

This surely does not imply that crystalline TeO exists. Materialscientist (talk) 23:16, 10 May 2013 (UTC)

Possibly references to TeO are emprical formulas?^King Jakob _C2 23:19, 10 May 2013 (UTC)

Possibly, but then it should be treated as TeO_x, with x=1±y, so what is the value of y? Materialscientist (talk) 23:22, 10 May 2013 (UTC)

Quoting old papers/books as evidence of the existence of a compound when modern research has not found it is not appropriate in an encyclopedia. At the risk of repeating myself (see above for reference on structure of DVD thin film and phase diagram) there appears to be no evidence for TeO. There is also appears to be no evidence for TeO_x where x is nearly 1. Unless a reference can be found that isn't a cave painting then this article should read "The diatomic molecule TeO has been found as a transient species (ref greenwood). Previous work that claimed the existence of TeO solid has not been substantiated (possibly refer to Viktor Guttmans book Main Group Elements: Groups VI and VII - Page 141-- and thats a book I haven't seen in a while!) The coating on DVD's called tellurium suboxide may be a mixture of tellurium dioxide and tellurium metal (ref Tyan et al doi.org/10.1063/1.3365880)" Short, accurate and with references--there I,ve nearly done it! Axiosaurus (talk) 19:04, 14 May 2013 (UTC)

Cut down to your version. There is simply no recent substantiated sources saying it exists. Double sharp (talk) 04:26, 8 September 2013 (UTC)

Indication that it exists. It has a CAS number. The other claims can be reworked to accommodate the fact that some are predicted.--Jakob (Scream about the things I've broken) 11:36, 8 September 2013 (UTC)

Existence of a CAS number is not a proof that a corresponding stoichiometric solid exists - for instance, look at the formula they give (Te=O, i.e., molecule). Materialscientist (talk) 11:46, 8 September 2013 (UTC)

And we do say that the TeO molecule exists. There is just no evidence for stochiometric TeO solid. Double sharp (talk) 12:40, 8 September 2013 (UTC)