Talk:Metallic bonding

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Wrong Information[edit]

Sorry, I don't know whether this is the right place to report errors.

The page says: Graphene is an example of two-dimensional metallic bonding. Its metallic bonds are similar to aromatic bonding in benzene, naphthalene, anthracene, ovalene, and so on." From what I have learned, Graphene does not bond by metallic bonding. It bonds by a creating a hexagonal structure with covalent shared electron bonds between each carbon atom, rather than having cations in a delocalised sea of electrons. — Preceding unsigned comment added by 60.242.239.208 (talk) 06:56, 13 March 2016 (UTC)

Untitled[edit]

can anyone please explain in more detail the following sentence which is part of the article: "the electrons involved in that interaction are delocalized across the crystalline structure of the metal" Thanks —The preceding unsigned comment was added by 82.25.189.23 (talkcontribs) 09:29, 30 September 2006 UTC-7.

the metal naturally forms a crystal structure that usually has many zones (another topic). but across the entire sample of metal, the metal nuclei are in various places and the valence electrons swarm about all nuclei, effectively bonding every nucleus to every other one. because of that, the electrons are delocalized meaning they are in even more random places than usual, belong to no single atom, and are more impossible to find Arc88 04:01, 21 December 2006 (UTC)

Name[edit]

Would it be better to move this to metallic bonding, to tie in with the opening words and the related category? Honbicot 21:59, 18 August 2007 (UTC)

If there are such things as metallic bonding and metallic bonds, why am I redirected from "Metallic bonding" to "Metallic bond", which begins by discussing, not the metallic bond, but metallic bonding? I like the idea of chemical bonds falling into neat categories. "Metallic bond" makes sense, no matter how nebulous the conceptualization. But this article, even if it does little more than to introduce the concept of metallic bonding under a heading elsewhere in cyberspace, ought to address "metallic bonds" per se, and right up front, in my jaunty opinion. D021317c (talk) 14:26, 20 November 2007 (UTC)

Apples and oranges[edit]

Of metallic bonds, I read (marvelously) that they may be compared to molten salts. How can pourable substances like molten salts be likened to countable links among discrete objects? It's not that I don't sense an analogy, but that it shouldn't go unexplained. I think what is meant is that the charge of free electrons in a metal is delocalized, as it is in a molten salt. Right? Would it be accurate to say, then, that the bonds among atoms in metals can be compared to the bonds among atoms in molten salts? I wonder how comparable they are to the bonds among dissociated salt ions in water. I wonder whether the charge can be considered an electron cloud, like that surrounding the nucleus of an atom, and to what extent the analogy might hold. D021317c (talk) 14:26, 20 November 2007 (UTC)

Removal of edits 28/11/2008[edit]

Theses edits were not vandalism and were well intentioned, I hope that that anonymous editor will join the wikipedia chemistry as they seem to have have good chemistry knowledge. The point was being missed that metallic bonding refers to the delocalised bonding found in bulk metal- (solid and liquid) and is different from covalent , "electron pair" metal-metal bonding exhibited by many elements including gallium, indium, cadmium, magnesium, zinc, mercury and others. --Axiosaurus (talk) 10:06, 28 November 2008 (UTC)

Looking for a date[edit]

Why are there no dates in the "history" section? Is that not the essence of history? SpinningSpark 16:26, 4 May 2009 (UTC)

Examples[edit]

Maybe you can put some examples of Metallic Bonds. It would be useful. —Preceding unsigned comment added by 187.35.176.81 (talk) 17:50, 17 January 2010 (UTC)

Name change to Metallic bonding?[edit]

Since the article itself states that a single "metallic bond" does not exist and that it is preferable to use the term metallic bonding, what about a name change from the former to the latter? —Kri (talk) 22:42, 3 November 2011 (UTC)

Since no one objected to my suggestion I took the freedom to perform a name change from Metallic bond to Metallic bonding. —Kri (talk) 23:16, 12 November 2011 (UTC)
Hm, it seems like Metallic bonding already exists as a redirect page, may a name change of this article have been done before? —Kri (talk) 23:23, 12 November 2011 (UTC)

Britannica uses "metallic bond". Google books have 60,800 hits for "metallic bond" and 53,500 for "metallic bonding" (which might be used in a separate meaning), thus I would keep the title as is. The article itself, in its current poorly sourced state, can't really be used as a justification. Its naming argument is based on "logic" which is often beaten by common use. Materialscientist (talk) 23:41, 12 November 2011 (UTC)

The nature of metallic bonding[edit]

The combination of two phenomena gives rise to metallic bonding: delocalization of electrons, free electrons wondering in the metal lattice; and the availability of a far larger number of delocalized energy states for such free electrons. The latter could be called electron deficiency. To shut a criticism up, namely [1], is easier than to improve articles. Does anybody of local frequenters know about such thing as the conduction band? I think user:Materialscientist should know it, and in any case one can read… so, this band in a crystalline material consists of delocalized electron states entirely: this is its distinction from the valence band. There is certain class of substances known as semiconductors; IMHO the majority of readers heard about it something. In this substances most electrons under normal conditions reside in the valence band, but there are (relatively few) electrons in the conduction band also. These delocalized electrons occupy only a tiny portion of the conduction band that, I repeat, comprises a vast space of (mostly empty) delocalized electron states. The question is: do semiconductors, such as the crystalline silicon, demonstrate metallic bonding? The answer is, surprisingly, no. Incnis Mrsi (talk) 21:08, 12 February 2014 (UTC)

I do not say there is not any metallic bonding in silicon. I say it does not demonstrate it: the crystal is bound covalently, with a negligible (if any) contribution from the conduction band electrons. That’s why the statement needs a clarification: something like that “amount of metallic bonding” is proportional to the number of conduction electrons.
There is yet another question: how strongly delocalized electrons are counted as delocalized? Is aromaticity a kind of metallic bonding? I’m not a chemist, but IMHO it isn’t. Incnis Mrsi (talk) 21:27, 12 February 2014 (UTC)

By the way, I knew for a long time that α-tin, a low-temperature allomorph, is a semiconductor whereas a high-temperature β-allomorph of tin is a metal, but I didn’t meditate why the dependence has namely this sign. In this context it is clear: when the Fermi–Dirac distribution sends sufficient number of electrons into the conduction band, a covalently bound structure cannot withstand the loss of bonds and metallic-bound one prevails. Incnis Mrsi (talk) 12:00, 15 February 2014 (UTC)

Can this be right?[edit]

...in the case of liquid gallium the stacking is not regular, at least not at long range and bond angles are easily changed...

But it's a liquid -- why would we expect crystal-like stacking? — Preceding unsigned comment added by 84.227.250.30 (talk) 05:59, 26 May 2014 (UTC)

This is misleading and will be changed. There is no stacking in a liquid; only an average short range order (see: Structure of liquids and glasses) Mgibby5 (talk) 02:00, 4 March 2015 (UTC)

The nature of metallic bonding seems confused and incorrect[edit]

@Dirac66: The section "The nature of metallic bonding" seems to confuse the organic chemistry definition of delocalization with the notion that electrons are free from the potential wells of the atoms (also called delocalized) to conduct electricity. Then there is the mention of boron nitride to show that this "delocalization" (again I assume it means resonance delocalization) is not sufficient. From what I know, isn't the organic resonance delocalization phenomenon completely irrelevant to metallic bonding, with electron mobility due to partially filled conduction bands (electron deficiency not as important IMO) as the determining factor? What other factors are there?--Officer781 (talk) 06:53, 25 May 2015 (UTC)

From Talk:Valence band and Talk:Conduction band it seems this issue is a bit more pervasive. We seem to have a bigger problem here.--Officer781 (talk) 10:22, 25 May 2015 (UTC)
The difference between the two types of delocalization would be the distances over which the electrons are delocalized. In small organic molecules there is delocalization only within the molecule, so that the phenomenon can be approximately described as a superposition of a few resonance structures, and the resonance description of (for example) benzene or naphthalene is simpler than the MO description. For a metal on the other hand the electrons can be delocalized over a macroscopic distance, so a resonance description would require an enormous number (like 1020) of structures and is totally impractical, and we use instead band theory which is analogous to an MO treatment. Dirac66 (talk) 20:50, 25 May 2015 (UTC)
@Dirac66: @Officer781: This is a very useful conversation, and I think we all agree this page could use further clarification. I would be very careful to in describing band theory as analogous to MO theory. MO theory describes localized electrons, the other delocalized Bloch states. There is a very fundamental distinction there, and at least within the talk pages we should feel free to be as exact as possible. I would agree that boron nitride is not an example of metallic bonding. A better distinction should be made between systems which exhibit metallic conduction (i.e. systems which have a delocalized band at the Fermi level) and systems which exhibit metallic bonding (i.e. systems which are the subject of this article). Boron nitride is an example of a system with covalent bonding but metallic conduction (although I think this should be checked... I previously though 2D BN was not metallic). Same with graphite and graphene (although the physics of graphene conduction are fairly unique and should not be put in the same bucket, also a confusing aspect of this article). Would anyone want to take a swing at furthering this distinction? Mgibby5 (talk) 17:39, 9 June 2015 (UTC)

Changing Article's quality rating to B Class[edit]

After reading this article, it seems to be fairly misleading, with some factually incorrect information, and not particularly well-structured. As such, I move to demote this article from B class to C class. I will work to improve this article as I have time in the future, but this may be some months before I can devote proper attention to it. I have been bold and demoted the article, but welcome discussion from anyone who would like to be involved in a structured re-write.Mgibby5 (talk) 03:49, 27 January 2016 (UTC)

I agree. For an important article like this it is in dreadful shape. Poorly referenced, full of misconceptions and unstructured, we could almost stub it and start again. Sigh. --John (talk) 21:19, 27 January 2016 (UTC)

This article needs help.[edit]

I'm new to Wikipedia, but this article is definitely not C class in my opinion. I don't know what I'm supposed to do to submit this for moderation, nor do I have the experience in this field to improve the article. Just thought I'd leave my two cents. --Mornarben (talk) 14:45, 17 May 2016 (UTC)

Assessment comment[edit]

The comment(s) below were originally left at Talk:Metallic bonding/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

This article reads a little strangely. For example:

"The nature of metals has fascinated humankind for many centuries, because these materials provided special people with tools of unsurpassed properties both in war and in peace. The reason for their properties and the nature of the bonding that keeps them together remained a mystery for centuries, even though great progress was made in their preparation and processing."

I don't think lines like the first one have a place in an article about metallic bonding...


Hi,

i really like this article on metallic bonding. Not many wikipedia articles on science are so thorough as this one wherever they need to be. 117.201.49.95 (talk) 09:44, 24 June 2010 (UTC)

Substituted at 21:52, 26 June 2016 (UTC)