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Where actually should be D and A in the inline scheme

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In D-H...A and D-X...A inline schemes, D and A seem to be not an electron donor and an electron acceptor, respectively, as they are described as the opposite in the following text. Does this mean they are "donor" and "acceptor of hydrogen/halogen bond" (i. e., is this a kind of terminology specific for this type of bonding)? Then probably this should be noted in the article for not to confuse such dummies as me. Thanks for your comment in advance. --Esmu Igors (talk) 15:11, 26 January 2012 (UTC)[reply]

So I dared editing by my own. BTW, the section I edited contradicted, as it seemed to me, even with the next sections of the same (i. e., this) article. --Esmu Igors (talk) 07:53, 28 January 2012 (UTC)[reply]

Shame, shame, was consulted by my organic chemistry professor and had to edit again. Neverthesless it requires more editing... --Esmu Igors (talk) 09:15, 3 February 2012 (UTC) --Esmu Igors (talk) 22:40, 3 February 2012 (UTC) corrected a mistake in comment[reply]

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The exact text "In 1814, Jean-Jacques Colin described the formation of a liquid — with a metallic lustre — when he mixed together ammonia and iodine." was found on the description of the page http://www.nature.com/nchem/journal/v6/n9/full/nchem.2042.html?foxtrotcallback=true at Google. The edit is from this year and the Nature's articles was published 3 years ago.--190.55.2.97 (talk) 03:02, 27 September 2017 (UTC)[reply]

Fixed. Bernanke's Crossbow (talk) 00:23, 6 August 2022 (UTC)[reply]

Strength?

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In the article, I wrote that most halogen bonds are stronger than hydrogen bonds. This is not exactly faithful to the sources, which say (repeatedly) that halogen bonds are weaker.

Here's why I'm confused, and departed from the sources.

Metrangolo et al "Hydrogen bonding in supramolecular chemistry" describes halogen bond strength 10–200 kJ/mol (see p. 3). Unless there's an error in the paper, those aren't extreme values — they're typical ones.

The examples given in Hydrogen bond § Bond strength suggest that typical hydrogen bonds are ~5 kcal/mol, which is the low end of Metrangolo's range. On the other hand, the same section also says that "those that are 15 to 40 kcal/mol, 5 to 15 kcal/mol, and >0 to 5 kcal/mol are considered strong, moderate, and weak, respectively." (Multiply by about 4 to get kJ/mol.) This suggests that almost all the examples cited are weak hydrogen bonds, which would be poor practice on that article, if true.

Also, halogen bonds are definitely more sensitive to direction. If direction is roughly random, then the expected strength of a strong-but-sterically-sensitive bond is smaller than the expected strength of a moderate-but-sterically-insensitive bond. Perhaps that's what the sources mean?

It would be nice if somebody could clear this up. Bernanke's Crossbow (talk) 00:22, 6 August 2022 (UTC)[reply]

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