Talk:Pentacarbonylhydridomanganese

Confusion

I edited this article for concision. It now says, in part (citation deleted):

A common reaction involving HMn(CO)₅ is substitution of the CO ligands by organophosphines, as occurs both thermally and photochemically. In this way the following derivatives form: MnH(CO)₃[P]₂, MnH(CO)₂[P]₃, and MnH(CO)[P]₄, (where [P] = P(OEt)₃, PPh(OEt)₂, PPh₂OEt, PPh(OiPr)₂).

This is confusing, with all those so-called chemical symbols (SCCS) that don’t represent elements! Using “[P]” is confusing: P = phosphorus; and the brackets “[]” seem out of place, you don’t normally need brackets (of any shape) around a single entity in order to denote order of operations. (Here they presumably denote that the thing isn’t phosphorus; still, the brackets seem at first glance, to be out of place, and there is still the confusion with phosphorus.) Et = ethyl (C₂H₅), and Ph = phenyl (C₆H₅ i.e. the benzene radical); i suppose? What is “Oi”? Pr = propyl, i suppose? If so, “Pr” should not be used; it should only be used to mean praseodymium. The Wikipedia article should say what these SCCSs mean! (Unfortunately, the source cited is a book rather than a website, so it is harder to verify from the source, what the SCCSs mean.)

Even if the SCCS “Pr” means propyl, or C₃H₇, then does it necessarily mean n-propyl ([CH₂]₃H, i.e. propane with a hydrogen atom removed from the carbon atom at either end)? Or might it also refer to isopropyl (CH[CH₃]₂, i.e. propane with a hydrogen atom removed from the central carbon atom)? Likewise, there are two types of propyl alcohol aka propanol: n-propyl alcohol, HO(CH₂)₃H; and isopropyl alcohol, CHOH(CH₃)₂.

And to make it easier to read, these SCCSs should be marked somehow, to show that they are not normal chemical symbols. (I once saw the SCCS “R” for “radical” or “rest [of molecule]”; i was confused because no element goes by the symbol “R”.) For Ph = phenyl, i recommend “Φ” (which has been used for phenyl); people will immediately know that this is not a normal chemical symbol. For Et = ethyl, i suggest “É” or “Ét”; the written accent would immediately alert the reader that this is not a normal chemical symbol. And if “Pr” means anything other than praseodymium, then it has to go; i suggest Př (the character ř, is borrowed from Czech).

Likewise, i recommend, as does IUPAC, that deuterium and tritium should go by the chemical symbols ²H and ³H respectively; not the SCCSs “D” and “T” respectively. “D” and “T” are not on the periodic table, so there is the same potential for confusion as with the SCCS “R”. And the notation “²H” and “³H” would mean that all isotopes of hydrogen would go by the same chemical symbol (H); just as with every other element, all isotopes of the same element go by the same chemical symbol. Solomonfromfinland (talk) 01:05, 7 April 2024 (UTC)

Luckily, i found an abstract of the source: “Synthesis, Characterization, and Reactivity of Cationic Molecular Hydrogen Complexes of Manganese(I)”. Unfortunately, while said abstract givs said confusing formulas, it does not explicitly say what the SCCSs mean, so, frustratingly, i cannot rule out the possibility that “Pr” here really means praseodymium. Also, said abstract uses SCCSs beyond than what said passage on Wikipedia currently includes; said abstract also has places where i truly can’t tell if “P” means phosphorus or one of the things denoted “[P]” in said passage on Wikipedia.

Another thing: the Wikipedia article uses the SCCS “Oi”. Said abstract spells it with a superscript: Oⁱ; in which case what does the superscript “i” mean? Or is it superscripted by mistake? Also: i said the source was a book. Actually, i now think it may be a journal article.

One possible solution: do an internet search, for other sources that support the same factoids, and which do not leav any SCCS unexplained.--Solomonfromfinland (talk) 01:31, 7 April 2024 (UTC)

Actually, i now think that the superscript “i” means iso-: isopropyl. If said hypothesis is correct, then “Pr” must mean propyl, not praseodymium. Still, the source’s notation is quite confusing, and Wikipedia should replace it with something less confusing.

Also, i think i found a source that explains what all those SCCSs mean.--Solomonfromfinland (talk) 02:47, 7 April 2024 (UTC)

Fix

I think i fixed it.--Solomonfromfinland (talk) 03:44, 7 April 2024 (UTC)

One of the under recognized benefits of Wikipedia is that it provides an outlet for us to give speeches and lecture the unclean. --Smokefoot (talk) 12:41, 7 April 2024 (UTC)

Yes, i gave a big lecture, on the need for chemical notation that isn’t confusing; and on why so-called chemical symbols (SCCS) (or “abnormal chemical symbols” [ACS], as i also call them), at least as currently used, ar a bad idea. Anyway, thank you, Smokefoot (if it was you who made the edit), for editing the relevant passage further for clarity and concision. Last time i checked, the part, “R here need not be a purely hydrocarbon component; it may, for instance, be OEt, where Et = ethyl group”, is still there. It should be be left there, so that future readers ar not confused. Still, i slightly resent the fact that the source for those chemical expressions, doesn’t explain what those SCCSs mean; what i resent even more, is that said source creates further confusion by using “Pr” to mean something other than praseodymium.

The source that i originally cited, to verify what these SCCSs mean, was deleted; however, i will list it here, for future reference:

Organic Chemistry: Second Edition, by Jonathan Clayden, Nick Greeves, and Stuart Warren. Oxford University Press, 2012.

I found said source online as a PDF. On page 23, i verified that Et = ethyl, and Pr = propyl. On pages xv-xvi, it has a list of abbreviations, which include Et = ethyl, and Pr = propyl, and Ph = phenyl. Page 24 further confirms that Ph = phenyl. Said book uses SCCS surprisingly often; and unfortunately, willingly uses ones that conflict with symbols of real elements, such as Pr for propyl, or Ar for aryl.

For further reading on Wikipedia about SCCS, see:

• “Chemical symbol”, where the sections “Symbols for named isotopes” and “Other symbols”, discuss SCCS. The latter section lists some SCCSs that conflict with symbols for real elements, e.g. Ac = acetyl, Am = amyl, B = base, Np = neopentyl.
• “Skeletal formula”: has a section titled “Pseudoelement symbols”: another possible term for SCCS.

SCCSs ar particularly annoying because there is good reason to believ that many elements beyond oganesson (EBO) (see “Extended periodic table” and “Category:Hypothetical chemical elements”) ar possible. True, ²⁹⁴Og, the only known isotope of oganesson, is very short-lived, but this is a badly neutron-deficient isotope; based on known trends, the longest-lived isotope of Og might hav mass number ~ 320; so there is a good chance that Og will hav an isotope with half-life > 1 year. If an SCCS doesn’t conflict with the chemical symbol (ChS) of a known element, it might conflict with a proposed ChS of an EBO. In fact, this was a problem for tennessine: they thought of giving it the ChS “Tn”, but that can mean “thoron” (radon-220, see “Isotopes of radon”); “Ts” can mean tosyl, but it was accepted as the ChS for tennessine anyway. I actually resent the fact that they chose “Ts” instead of “Tn” for tennessine. I think we should name one EBO “teslium”, after Nikola Tesla. But what would be the ChS for “teslium”? Te = tellurium, Ts = tennessine, Tl = thallium, Ti = titanium, and Tm = thulium; leaving only “Tu”, which would look ugly and unconvincing and would hav been more appropriate as a ChS for tungsten or thulium. (And what if they had decided that tungsten = Tu? Then there would be no ChS available for “teslium”.) This debacle would hav been avoided if tennessine = Tn; then “teslium” could be Ts. My solution is that “teslium” would hav the ChS “T”. But this conflicts with T = tritium. So i, with good reason, resent T = tritium, Tn = thoron, Ts = tennessine, and (to a lesser extent; partly but not entirely due to guilt by association with T = tritium) D = deuterium. After all, if T = tritium is unacceptable, then D = deuterium should also be unacceptable.--Solomonfromfinland (talk) 03:52, 9 April 2024 (UTC)

You are preaching without asking. That is a tricky combination. Smokefoot (talk) 20:32, 9 April 2024 (UTC)

My apologies. Solomonfromfinland (talk) 22:30, 9 April 2024 (UTC)

These articles that you are attacking were written by flawed editors. They took the time to create these articles that are templates for other more perfect souls to improve. One other thing, chemistry is a culture populated by tens of thousands of people over centuries of activity. Inevitably their communication styles have quirks and specializations that are not immediately advantageous to the nonchemists (like you). These quirks are used to expedite and accelerate communication within the chemical community at the risk of being somewhat opaque to the nonchemists. It's a trade-off. But there is no reason for an nonchemist to barge into this sophisticated culture with both pistols drawn shooting at small peculiarities. Maybe keep the pistols holstered and ask the locals about their communication style. The chemists would probably point you to our manual of style and help you make their articles less opaque. --Smokefoot (talk) 13:50, 10 April 2024 (UTC)