Talk:Metal

Sulfur nitride - a metal molecular compound

I removed sulfur nitride from the lede. It's considered a non-metal with some metallic properties. Its inclusion as a metal contradicts a) this article, b) the sulfur nitride article c) formal reference works on the topic. Its original inclusion in 2019 was unreffed. Ordinary Person (talk) 04:47, 12 June 2022 (UTC)

I reverted this edit on June 20th and added supporting citations. Sandbh (talk)

Other metal molecular compounds

Are there less controversial metal (or metallic) molecular compounds ? - Rod57 (talk) 12:10, 12 March 2024 (UTC)

Graphite - is it a metal

Can we clarify if graphite is considered a metal, Since it conducts electricity moderately well and seems to have the general characteristics (of a metal) in the introduction. Or, Is it too soft to be a metal ? - Rod57 (talk) 12:17, 12 March 2024 (UTC)

Physics definition

Article says "In physics, a metal is generally regarded as any substance capable of conducting electricity at a temperature of absolute zero.[2]" - Is it "generally regarded" or just one persons idea ? It's a very theoretical definition rather than being something that can be tested or measured. If true, it would make all materials, while superconducting, metals. A more usual definition of a metal might be having free electrons in a conduction band ? - Rod57 (talk) 12:33, 12 March 2024 (UTC)

The source is Nevill Mott. If you have another source, please let's have it. Johnjbarton (talk) 15:28, 2 May 2024 (UTC)

Electrical and thermal: Plutonium

The electrical and thermal section read, in part:

"Plutonium increases its electrical conductivity when heated in the temperature range of around −175 to +125 °C, with anomalously large thermal expansion coefficient and a phase change from monoclinic to face-centered cubic near 100 °C."

The source was given as Hecker, Siegfried S. (2000). "Plutonium and its alloys: from atoms to microstructure" (PDF). Los Alamos Science. 26: 290–335.

Reading the source, it does not say anything about:

• Pu increasing its electrical conductivity when heated in the temperature range of around −175 to +125 °C; nor
• an "anomalously large" thermal expansion coefficient.

Nor did the article's citation give a page number/s specifying where the pertient facts were mentioned.

OTOH, Russell AM & Lee KL 2005, Structure-Property Relations in Nonferrous Metals, Wiley-Interscience, New York, p. 466, say that when Pu (a metal) is heated within a temperature range of 100 to 400K [–173 to 126.85 °C] its conductivity increases.

The same source shows that the simple monoclinic phase of Pu is stable below 122 °C (p. 465).

I have therefore amended the mention of Pu to read...

"Plutonium increases its electrical conductivity when heated in the temperature range of around −175 to +125 °C"

...and added a citation to Russel & Lee, with a page number.

Since the fact that Pu undergoes a phase change from simple monoclinic to body-centred monoclinic is not germane to the point about its unusual tempertaure coefficient of resistivity, I've removed it. --- Sandbh (talk) 13:03, 20 June 2024 (UTC)

Please do more reading on fundamental physics, and careful analysis, see for instance https://www.rmcybernetics.com/science/diy-experiments/heat-and-resistivity#:~:text=The%20temperature%20affects%20the%20dimensions,flow%20than%20a%20thinner%20one or many other introductions to physics. With anomalous expansion, as in Pu this will have a large effect. Ldm1954 (talk) 11:24, 22 June 2024 (UTC)

Disputed cite: Nonmetallic materials do not have electrons available at the Fermi level

The lede says:

A metal (from Ancient Greek μέταλλον (métallon) 'mine, quarry, metal') is a material that when polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not.^[1][2]

Neither cite [1] not cite [2] say that nonmetallic materials do not have electrons available at the Fermi level.

[1] Kittel, Charles (2018). Introduction to solid state physics. Paul McEuen (Global edition, [9th edition] ed.). Hoboken, NJ: Wiley. ISBN 978-1-119-45416-8. [2] Ashcroft, Neil W.; Mermin, N. David (1976). Solid state physics. New York: Holt, Rinehart and Winston. ISBN 978-0-03-083993-1.
— Sandbh (talk) 04:28, 28 June 2024 (UTC)

@Ldm1954: In this edit [1] the reasons you gave for removing the disupted tags were:

"Added specific chapters. Those exact words are not used, but the science explained in those chapters is equivalent. It matters to read and understand."

Your reasoning breaches WP:NOR i.e. no orginal research. Neither source explicitly makes the statements concerned. --- Sandbh (talk) 13:20, 29 June 2024 (UTC)

Neither source has to make exactly that statement. What is included is a rephrasing which is covered in all solid state physics books. Unfortunately you believe that sources must be verbatim, this is wrong. If you want to challenge this I will post on WP:PHYSICS, I know what the response will be. Ldm1954 (talk) 13:49, 29 June 2024 (UTC)

Update suggestions welcome

Please comment here, or just edit. Ldm1954 (talk) 13:44, 19 July 2024 (UTC)