Jump to content

Talk:Skeletal formula

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia

Additional picture?

[edit]

Just a thought, if anyone wants to agree/disagree - since this is all about skeletal formulae, should we have an atom labelled formulae with it? (for example File:Escitalopram-nonskeletal.gif)

Could be an interesting contrast, yes. You forgot the fluorine, though :) Any chance the image could be saved as a PNG? GIF is not really the best format. Fvasconcellos (t·c) 14:16, 23 May 2008 (UTC)[reply]

Bond Line Formula

[edit]

Skeletal Formula is also known as bond line formula. Should there be a redirect or some other notation indicating this? Nilboarder 04:02, 2 October 2006 (UTC)[reply]

Drawing skeletal structures by computer

[edit]

What program is everyone using to draw the 2D skeletal formulas anyway?

See molecule editor for some possibilities.
Ben 18:18, 24 March 2007 (UTC)[reply]

Funny little "crossed line"?

[edit]

This crossed line business is HORRENDOUS - certainly not acceptable in the ACS style and I'd be surprised to find it acceptable according to IUPAC. If you used that notation at Cal, you'd be laughed out of the room! I've read thousands of articles in the field and have never in my life seen that notation before encountering it here today. If it's not supported by citation which shows it to be approved according to IUPAC then I'll be removing it later in the week. FOR SHAME!!!!!! —Preceding unsigned comment added by 24.130.82.154 (talk) 07:28, 12 January 2011 (UTC)[reply]

This is a computer software thing and you are right that IUPAC does not accept it. The standard ways to do this are either to draw a linear double bond (e.g. CH3CH=CHCH3 for but-2-ene, but not specifically (2Z)-but-2-ene or (2E)-but-2-ene), or to use a wavy bond adjacent to the double bond (this wavy bond however must not be attached to another stereogenic centre). Double sharp (talk) 04:06, 31 July 2016 (UTC)[reply]

In sinigrin there's a crossed-over bond to the nitrogen; I'm not sure what this is and this article, although finally explaining the "squiggly line" even my chem teacher couldn't explain, was not helpful. If anyone can explain what the crossed-over bond means (I suspect it means CN?) perhaps it would be a nice addition to the article. WnC? 17:36, 9 April 2009 (UTC)[reply]

I'll write a bit about it tomorrow. The crossed bond means undetermined or deliberately ambiguous E/Z stereochemistry at the double bond, i.e. it could be either E or Z or a mixture of both.
Ben (talk) 00:45, 10 April 2009 (UTC)[reply]
OK, thanks for clarifying! WnC? 12:14, 10 April 2009 (UTC)[reply]

Lewis Formulas

[edit]

I don't agree that the ethanol structure identified as a "Lewis Formula" actually is a Lewis Formula. A Lewis Formula, as noted elsewhere in the same article, shows the shared electrons comprising a bond as dots, not as lines. The convention using lines to represent chemical bonds was systemitized by Emil Fischer in the Fischer Projection Formula, wherein the horizontally depicted bonds around carbon project out of the plane of the page and the vertical bonds project behind the plane of the page. Although Fischer applied this specifically to chiral molecules like sugars and amino acids it is correct also for achiral molecules like ethanol. Prostaf2alpha (talk) 04:39, 3 May 2009 (UTC)[reply]

ASCII-art formulae?

[edit]

As an alternative to graphical representative of the skeletal formulae, you can with some success represent it using ASCII characters, like this:

Caffeine

   CH3
    |
  N_|_N  O
 // || \//
 \N_||_N/\
 /        CH3
H3C

This is not a very accurate and detailed method of representation, but you can use it for your purposes when you are unable to show a picture or draw a diagram of the formula. How about adding this to the article? Anton Pirogovski (talk) 18:48, 5 December 2009 (UTC)[reply]

Skeletal diagrams are reversed!

[edit]

My apologies. I finally found an introductory online text that clearly explains it doesn't matter which way the diagrams are drawn, as long as they're consistent. I'm so used to counting from the left.

I'll update the page with this information.

Cephas Borg (talk) 04:02, 26 June 2014 (UTC)[reply]

What's being illustrated in this diagram from the Pinene article?

[edit]

Can someone explain the isometry that this is illustrating? The solid/dashed lines in the ring are what confuse me; is this illustrating that the ring is non-planar, and its angle relative to the plane? --BlueNovember (talk contribs) 19:57, 20 March 2015 (UTC)[reply]

The left two and the right two are pairs of enantiomers. The wedge (or dash) indicates that these two bond are above (or below, resp.) relative to the rest of the structure. Alsosaid1987 (talk) 07:38, 16 January 2021 (UTC)[reply]

Pn, Hx, Hp

[edit]

Never seen these before. Sources please? Double sharp (talk) 16:34, 30 July 2016 (UTC)[reply]

I also don't know exactly what those symbols mean. This Wikipedia article should explain what they mean, and cite a source (see Wikipedia:Verifiability). Btw, this article has a term for such symbols: "pseudoelement symbols"; the article has a section with that title. Solomonfromfinland (talk) 22:40, 19 April 2024 (UTC)[reply]

ChemDraw as de facto industry standard

[edit]

I don't think there's much doubt in this regard. For instance, if you look at Angew. Chem. Int. Ed.'s manuscript preparation standards, all chemical structures are to be submitted in Chemdraw .cdx format, embedded in the manuscript: https://onlinelibrary.wiley.com/page/journal/15213773/homepage/notice-to-authors#sect3ManuscriptPreparation

Alsosaid1987 (talk) 07:35, 16 January 2021 (UTC)[reply]

Pseudoelement symbols here?

[edit]

The inclusion of pseudoelement symbols in this page seems off-topic, and I feel as though they should have their own page. Anyone agree with me? It's also missing a few like Pc for phthalocyanine. Peptobismite (talk) 22:45, 4 February 2024 (UTC)[reply]

Well, creating a separate article dosent seem all that important as the search terms "Pseudo element", "Pseudoelement" and "Pseudoelement symbols" already redirect to that part of this article. Charcoal47 (talk) 10:49, 29 March 2024 (UTC)[reply]
Actually, i tested it just now, and there isn't and article or redirect called "Pseudoelement". (I didn't put a hyperlink here, on the term "Pseudoelement", because i think red links look ugly.) Solomonfromfinland (talk) 02:13, 14 April 2024 (UTC)[reply]

A lie!

[edit]

The section “Pseudoelement symbols”, lists a number of such symbols (abnormal chemical symbols [ACS] or so-called chemical symbols [SCCS], i call them).

Many of these symbols conflict with the symbol of an element, e.g. Ar = aryl or argon. However, in most of those cases, the article says that, for various reasons, said notation rarely if ever causes confusion. This is a lie!

  • An earlier version of the article “Pentacarbonylhydridomanganese”, used several SCCS, including “Pr”. The “Pr” genuinely confused me; i had real trouble confirming that it meant propyl not praseodymium. Other SCCSs used in the article, also confused me; i had to confirm that they meant what i thought they meant, e.g. Et = ethyl, Ph = phenyl. I complained about the matter on “Talk:Pentacarbonylhydridomanganese”.
  • The article “Tosyl”, at one point uses the symbol “Ac”; it annoys me that i can’t find anything that explicitly says that this means acetyl and not actinium; especially since actinium (unlike tennessine; Ts can also mean tosyl) has a known isotope (227Ac) with a half-life of over a year, and actinium is massively easier to procure than tennessine. (Btw, as i explained on “Talk:Pentacarbonylhydridomanganese”, i also resent the fact that they chose the chemical symbol “Ts” rather than “Tn” for tennessine.)
  • When i was a teenager (i was born in 1990), i saw the SCCS “R”, and i was confused; no element goes by the chemical symbol “R”; it took me some time to figure out that R meant “radical” or “rest (of molecule)”.
  • In the case of Pr = propyl or praseodymium, or Ar = aryl or argon, the potential for confusion should be even bigger than with e.g. Ac = acetyl or actinium; because praseodymium and argon, unlike actinium, are stable elements, and so should be massively easier to procure than actinium; in fact, argon is very plentiful in Earth’s atmosphere, while praseodymium is apparently more common in Earth’s crust than e.g. tin.

The symbols Et, Ph, and R, don’t even conflict with the symbol of an element, and they still caused me confusion! Solomonfromfinland (talk) 05:15, 10 April 2024 (UTC)[reply]

Making up jargon-names for a concept you don't understand is not helping here. It's okay not to understand something, but that's not necessarily because it's too confusing to be understood. Just like you have to learn element symbols, you have to learn that there are other short-hand notations used, and what they mean. For any given context, only one meaning is typically reasonable. It's annoying that you have to know something about the chemical before you can easily choose the correct meaning. It's not a science problem anyway. If I ask you to pronounce the English word "sow", there's a 50/50 chance you will not say what I'm thinking, but reading any given sentence where you know enough of the context, you can decide if it's /saʊ/ or /soʊ/. Wikipedia by policy lags and simply documents what is already happening and reported elsewhere, is not the place to vent about what you think IUPAC or other standards have wrong or try to fix it. DMacks (talk) 05:54, 10 April 2024 (UTC)[reply]