Talk:Indium trihydride

Indium trihydride - a solid

The lede says the polymeric form is a solid - in the article it is said to decompose at -90 C which is right? If the article is correct then the lede should be amended to state an unstable solid decomposing at whatever centigrade. Also there is no reference for the structure of the polymeric solid as being a 3D network- it probably is - but is there evidence? Also some idea of how the solid is produced would be useful- I assume it is from matrix isolated InH₃ which is allowed to warm up as decribed in the references. Axiosaurus (talk) 13:45, 24 September 2013 (UTC)

What do you mean "which is right?"? It's not as if the two factoids are mutually exclusive. Why would the lede need to be rewritten? I'll handle the other concerns. Plasmic Physics (talk) 14:13, 24 September 2013 (UTC)

When a chemist says that a compound is a solid they ensure that there is no confusion about whether this refers to the standard state by stating if it is unstable. It simply avoids confusion. Axiosaurus (talk) 18:47, 24 September 2013 (UTC)

By their very definition, network solids cannot exist in the liquid or gas phase. The closest they can come, are colloids or aerosols. When some network solids 'melt', they are actually decomposing into a mixture of simple chemical distinct molecules. Plasmic Physics (talk) 22:11, 24 September 2013 (UTC)

Recent edits

Nomenclature of Inorganic Chemistry: IUPAC Recommendations 2005

states that :

"Square brackets are used... To enclose the whole coordination entity of a neutral (formal) coordination compound."

and example 14 under section IR-4.3 yields the same use of square brackets as in use in the article. It is redundant to repeat facts through an article. Therefore, it is unnecessary to explicitly state that it is a polymeric solid twice; it is already explained that indium trihydride is produced by the uncatalysed autopolymerisation of indigane, which implies that indigane cannot persist undiluted. Plasmic Physics (talk) 10:02, 25 September 2013 (UTC)

The new acidity section

This new addition to the article covers the lewis acidity of indigane which is already covered in the article. The reaction is of InH₃ with a lewis base- not the "indigyl group". Axiosaurus (talk) 10:29, 6 January 2015 (UTC)

Fixed: relevant content has been collated. I'm aware of what I wrote, and I can assure you that it is the indigyl group. Plasmic Physics (talk) 11:07, 6 January 2015 (UTC)

Sorry I disagree. The formation of a complex of InH₃, LInH₃, requires a strange stretch of logic to be called a reaction of the "indigyl" group, H₂In- . Axiosaurus (talk) 12:40, 6 January 2015 (UTC)

Indigyl methanide, indigyl chloride... indigyl hydride, ergo, not such a strange stretch. Plasmic Physics (talk) 20:39, 6 January 2015 (UTC)

Indigyl as well as being a stretch - its the indium(III) center that is the Lewis acid. Also you should check who else uses the term indigyl to describe the -InH₂ group. Using this obscure and unfamiliar term obscures tye chemistry and makes the article less accessible.Axiosaurus (talk) 09:09, 7 January 2015 (UTC)

The immediate ligands have an important influence on the binding atoms within a Lewis acid. If those ligands are electron-withdrawing, then that Lewis acid tends to form weaker adducts. The same effect occurs for bulky ligands. (Obscures the chemistry), that is why there is a bracketed formulaic representation of the group. "Indigyl" is also the actual name, unless you want me to pull something out of thin air. Plasmic Physics (talk) 19:54, 7 January 2015 (UTC)

I have removed the bit about indigyl as this is not used by anyone else, so will not be verifyable. Graeme Bartlett (talk) 02:20, 19 June 2016 (UTC)

Polymer project

Yes its a polymer, if andrews et al are correct. Yes there is polymer project. However if you look at the project it is actually concerned with materials like PVC, thermo-setting plastics, rubbers etc etc. Low temperature hydrogen bridged polymers? Sensibly not relevant. Axiosaurus (talk) 16:38, 6 January 2015 (UTC)

Pure coincidence. They don't preclude inorganic polymers anywhere. Plasmic Physics (talk) 19:48, 6 January 2015 (UTC)

Solubility of indium trihydride polymer

Polymeric InH₃ decomposes above -90 -- I suggest that testing solubility in ALL solvents was not possible at temperatures below this. The perceived high school wisdom that network solids (hard high melting etc etc ) are insoluble doesn't apply to aluminium hydride - this is also a network solid yet is said to be soluble in THF and ether. A reference is required.

No polymer is soluble, polymers are decomposed/cracked by so called solvents, into smaller units, which are soluble. However these units are not usually chemically equivalent. This is what happens to aluminium hydride. It is not dissolution, it is a plain reaction, albeit reversible. Plasmic Physics (talk) 19:55, 6 January 2015 (UTC)

You are redefining the common usage of solubility. Certainly chemists who described aluminium hydride do not share your view. Axiosaurus (talk) 08:59, 7 January 2015 (UTC)

The sources speak of alumane solutions, they don't state that poly(alumane) is soluble. They clearly state that the precipitation event is non-reversible. The article is incorrectly written with false interpretations of the sources. Read any trustworthy article on covalent network solids, and you'll find the same - a statement to the effect of: no CNS can dissolve, as no solvent can easily form solvation complexes with the inherently large molecules that form polymers. Plasmic Physics (talk) 09:45, 7 January 2015 (UTC)

What are generally called covalent network solids are ( for inorganic examples) high melting strongly bonded compounds/elements e.g. diamond, silica etc. generally, but not always, (e.g. graphite) with two centre 2 electron bonds. Do you know of a review that includes hydrogen bridged networks? It is known that the In-H bond is not inherently weak, it is after all stronger than the In-C bond - but the In-H-In bridge seems to be very labile causing kinetic rather than thermodynamic instability hence the thermal instability of InH₃ complexes. As regards solid InH₃ being a network polymer Andrews work papers rely, experimentally, solely on I.R spectra interpretation. The structure requires further investigation to finalise its description. This is why I have changed the words on the structure to add a note of caution. Regarding solubility did Andrews manage to try dissolving his solid InH₃ samples?Axiosaurus (talk) 17:47, 7 January 2015 (UTC)

I do not know by heart of any reviews for anything. Do you know of a review that precludes them? Yes, Andrews rely purely on I.R. data, but that is sufficient to provide empirical evidence, proving that the aggregate is not simply an oligomeric structure, but polymeric instead. Even if the detailed structure remains unknown. Plasmic Physics (talk) 19:54, 7 January 2015 (UTC)