Talk:Hammett equation

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what constants to use[edit]

Hi 137.131.130.230, the original image contains the original Hammett values from his 1937 publication. You point to recent values for a good reason but your edit fails in execution. Do not expect the average wiki reader to have access to the literature that you cite (it at least requires a trip to a local university), a better solution would be to keep the original values as they are and then present a list of more recent and more generallt accepted values V8rik 23:14, 21 November 2006 (UTC)[reply]

I would add that a text list would be preferable to an image.Olin 00:15, 4 March 2007 (UTC)[reply]
I strongly agree the recent values should be included on the page more prominently than the 1937 values. The 1991 Chemical Reviews paper, cited in the notes, is a good source. Would edit myself, but I don't want to go through the trouble of handling the image.
Kanyegirl (talk) 19:59, 9 January 2008 (UTC)[reply]


  • I do not really see a problem, the image is there as a historical reference and if you want to add a table with modern-day data please feel free to do so. That will only enhance the article V8rik (talk) 21:48, 9 January 2008 (UTC)[reply]

merger of Rho value[edit]

I propose that Rho value be merged into this article. — Ksero t c 15:37, 7 November 2007 (UTC)[reply]

  • I agree, same topic V8rik 17:54, 7 November 2007 (UTC)[reply]
  • I agree, suggest keeping the title as Hammett eqn with redirect from Rho value Seansheep (talk) 21:45, 28 February 2008 (UTC)[reply]

section on the estimation of Hammett constants[edit]

"Estimation of Hammett Sigma Constants from the Core-Electron Binding Energy Shifts" This does not contribute to the article at all and should be deleted. It reads like a rather dull, on-a-tangent computational chemistry study (reads like someone is after a bit of self-promotion!). If this was Nature/Science quality science then it should included, but clearly it is not. This addition just serves to confuse the reader with another arbitrary constant to consider. Indeed, there are MANY ways of estimating Hammett constants simply because they correlate with so many molecular properties. I strongly suggest a delete. 24th Feb 2009 —Preceding unsigned comment added by 129.215.221.247 (talk) 20:47, 24 February 2009 (UTC)[reply]

  • if Wikipedia would delete all Nature/Science derived content there would be little left. No evidence for self-promotion. Moved section to the bottom V8rik (talk) 21:16, 24 February 2009 (UTC)[reply]

Missing hydrogen[edit]

Structure 2b in one of the schemes is missing the hydrogen attached to the charged carbon. It is implicit in 2a but it has to be explicit in 2b. Cheers. —Preceding unsigned comment added by 78.8.140.177 (talk) 22:46, 10 December 2010 (UTC)[reply]

Outsider's comment and question[edit]

I reached this page from article about involvement of students. Is an outsider permitted to comment? I wrote an undergraduate survey paper on Hammett's Law in 1946. Michael P. Barnett (talk) 02:43, 12 December 2010 (UTC)[reply]

  • Hi Michel, (you must have read the recent JCE article) you are not only free to comment on this page but you are also free to edit this article or any article. No permissions required! If you need any help contact me V8rik (talk) 17:24, 13 December 2010 (UTC)[reply]
As an addition to V8rik's comment, don't feel as an outsider. There is only one real requirement to be part of the community – wanting to make Wikipedia a better encyclopedia. If you are afraid that you'll break some rules (and there is quite a lot of them), don't be. Read Five pillars and if you make some mistake, it can be easily undone and you can gradually learn all the rules that concern you. Svick (talk) 15:14, 18 December 2010 (UTC)[reply]

Hammett Modifications[edit]

I think this section is extremely important and needs to be elaborated, also, renamed/organized differently. Listed in the article, "Other equations now exist that refine the original Hammett equation: the Swain-Lupton equation, the Taft equation, the Grunwald-Winstein equation, and the Yukawa-Tsuno equation" in no way tells the reader that these equations are actually trying to define σ. This was talked about briefly in the Nonlinearity part of the article but seemed out of place. — Preceding unsigned comment added by 100.2.1.225 (talk) 03:32, 2 October 2012 (UTC)[reply]

These equations already have dedicated articles (note the internal links) V8rik (talk) 21:31, 2 October 2012 (UTC)[reply]
I do see that they have dedicated articles but I feel that they should be presented in a way where readers understand their importance rather than regard them as a side note. Also, I did not see Brown and Okamoto listed for their σp+ parameters. A quick search on wikipedia did not list them, and I'm beginning to understand how complicated editing can be! I would have to organize my thoughts before I began to suggest any significant changes. — Preceding unsigned comment added by 100.2.1.225 (talk) 00:21, 3 October 2012 (UTC)[reply]

Plagiarism (copy-paste) claim posted[edit]

The appearance of section after section of tabular information without any source is not honest intellectual work. These numbers were drawn from sources, and until the source of each set of values is identified, for each table, the copy-paste should remain in place. Le Prof 50.141.73.138 (talk) 01:11, 23 June 2015 (UTC)[reply]

I have started posting standard intermediate and advanced Phys Org texts[edit]

…in the Further reading section. No editor at WP should be attempting to explain these very thoroughly described, historically important and exhaustively reviewed topics de novo (from scratch), returning to the original published primary sources, and describing/citing only them. If this is what is occurring, it should cease.

Alternatively and no better, it may be the case that some editor is proceeding from Isaacs, or Dougherty & Anslyn, or another advanced physical organic chemistry text, paraphrasing that content, pulling from it the information and the citations to the primary literature, but not citing that intermediate source of their conceptual presentations. If this is the case, it should also cease.

Even a decent synthesis of some combination of material from those two sources, plus Lowry & RIchardson, and Carey & Sundberg, and/or Smith & March will be beyond most editors here. But at least approaching the material in that way allows other editors and experts to verify and improve upon what is done. No editor of any merit and expertise will have the time to deconvolute something as badly unsourced, and paraphrased/cribbed as this appears to have been.We need editors to be excerpting/paraphrasing the explanations and descriptions of the experts from sound secondary sources in these specialized physical organic field, letting us know specifically, with full citation and page numbers where it was drawn from (so we can, per policy, verify the work)—and certainly not re-interpreting the original literature, writing out ones own interpretations. This is an encyclopedia, and in the sciences, purportedly based on good secondary sources (and not a an original essay or review draft for a course or publication).

Finally, and respectfully, if you cannot give the time to copyedit/proof your work—to catch yourself before you completely leave out half of a citation (see [full citation needed] tag placed in the article), or forget to capitalize "Hammett"...please do not post your material. It is simply rude to expect others to come after to cleanup the material enough to be presentable—even more rude than my direct speech here, insofar as it is like dropping your dirty laundry about, expecting nanny or mother to pick up. Le Prof 50.141.73.138 (talk) 01:14, 23 June 2015 (UTC)[reply]