Template:Did you know nominations/Molecular gyroscope

The following is an archived discussion of the DYK nomination of the article below. Please do not modify this page. Subsequent comments should be made on the appropriate discussion page (such as this nomination's talk page, the article's talk page or Wikipedia talk:Did you know), unless there is consensus to re-open the discussion at this page. No further edits should be made to this page.

The result was: promoted by Hawkeye7 (talk) 20:27, 15 October 2014 (UTC)

Molecular gyroscope

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... that the rate for inertially rotating (pictured) p-phenylene without barriers is estimated to be approximately 1,000,000,000,000 (one trillion) per second without barriers?

Reviewed: Theatres in Sutton

Created by Wnt (talk). Nominated by RTG (talk) at 16:35, 4 October 2014 (UTC).

It is new enough and long enough, a copyvio seems to be unlikely, but I had trouble verifying the hook. I looked at the cited source and the word trillion is not used, nor could I find anything specifically saying that the rate of p-phenylene is in fact 1 trillion per second. The paper does say that "3,5-di-tert-butyl substitution in each of the six trityl groups of compound 2 allows for phenylene flipping with a rate >10^8 [per second]", is that what was meant? Jinkinson talk to me 19:23, 4 October 2014 (UTC)

Hi, does it say 10¹²? I had to look it up also. It is ten to the power of twelve, twelve zeros, see Power of ten. Also, here is how to ping an editor for their attention {{reply|Jinkinson}} which does this ->@Jinkinson:. The power of ten article will tell you that "n" is the power, written like this 10ⁿ. then the table below will tell you if the power is 12, the number is 1,000,000,000,000 (and I am going to edit that table so that it says 10¹² instead of just 12). ~ R.T.G 19:46, 4 October 2014 (UTC)

I am looking at the 15th instance of "10" on the page where it says 10¹², but it is not quite clearly exactly the words in the hook, which may need a reword to the article and hook.. ~ R.T.G 19:50, 4 October 2014 (UTC)

Now I am looking at the third instance of 1012 on the page, and again it is not directly clear so I am going to ping the artcile creator to see if they can help @Wnt: ~ R.T.G 19:52, 4 October 2014 (UTC)

No, it is me that is wrong. the tert butyl modifier got 10⁸ while 10¹² was "without barriers", so I'll fix that in the hook with this edit. ~ R.T.G 19:58, 4 October 2014 (UTC)

@RTG: Hmmmm, I just wrote the first draft and there are a few tricks about this I haven't gotten clear yet. The biggest problem is that this is a thermal phenomenon but I'm not entirely sure if this is at 65 C or at 300 K or at 241-285 K, all of which are mentioned. My assumption - but I'm not an expert - is that the rate doesn't change much because it's going to be an energy determined by kT, with velocity according to square root of Kelvin temperature, but it makes me nervous to assume that. Also, there are some shifts in this paper from two-site exchange rate to preexponential factor to exchange rate and I'm not sure there aren't some coefficients involved in translating one to the other. So especially if we're going to feature a hook I want to ground it pretty solidly, i.e. quoting the article's summary of another article, "a rotational frequency of 2.4 x 10¹² s⁻¹ calculated for a phenylene free rotor from its moment of inertia along the 1,4-axis." I should then refer this back to the source the paper cited, Kawski, A. Crit. ReV. Anal. Chem. 1993, 23, 459-529 [1] but the site is telling me to bugger off. Still, it was a calculation for biophysics, so I'm pretty sure it's room temp or something close. (The first paper also says "(ca. 10¹² s⁻¹)", and comes to a (primary) result of 1.7 x 10¹² which it says is "in good agreement") Anyway, I'm thinking more like ALT1 ... that in the absence of energy barriers, p-phenylene in a molecular gyroscope (pictured) at room temperature is predicted to rotate over one trillion times per second? Also please note that the image above is not at all related to this compound. We could copy an illustration of this compound as a mere chemical formula, but it ought to be made up from scratch, better than the pretty low quality dot-matrix like graphic in this paper. Wnt (talk) 21:01, 4 October 2014 (UTC)

@Wnt:Seven or so DYKs will go up and only one picture will be used; they count the hits of the pictures for a hall of fame so tabloid stuff and art, and gruesome stuff, etc get the hits (<-that's not an experienced opinion btw). However, regarding the hook and trying to generate clicks, I think that "...1,000,000,000,000 rotations per second..." is more attractive than "...a trillion rotations per second..." simply because if 1,000,000 is the biggest number you see regularly, you'll look at that number and think (billion? trillion? gazillion? dazzle-illion?) and click it just to see :) ~ R.T.G 22:08, 4 October 2014 (UTC)

Well, I'll admit I've had small stats on my DYKs, but I don't really care (I probably wouldn't even have bothered going through this process). You can try what you want, but I'd think you should consider reworking the hook a little (maybe something simpler like "that thermal energy at room temperature can spin a molecular gyroscope at more than 1,000,000,000,000 times a second") But using commas in a numeral is a U.S.-ish style not followed in much of the world (I think the Brits and all other English speakers have taken to using our definition of trillion though ... haven't they?) Wnt (talk) 22:38, 4 October 2014 (UTC)

It has gone thousand, mill, bill, trill for a long time. But the hook with the fact that it is powered by room temperature, that really is a catchy hook. I am sure it will get a few thousand hits. ~ R.T.G 22:51, 4 October 2014 (UTC)

I think numbers much over a million tended to be irrelevant when those numbers were used. In recent years it is not unusual to see the word "trillion" ~ R.T.G 22:53, 4 October 2014 (UTC)@Jinkinson:

How about file:Mol-gyro.png as an image? I think it's the key structure from ref 2 (compound 3a in doi:10.1021/ja064325c) mentioned in the second row of the table. I'm open for suggestions on alternate coloring (accessibility or any other reason for this use-case of it). Might be nice to have a gallery of each of the main examples, all using the same style and color-coding. I can try to pull the actual X-ray data to generate a 3D rendering rather than the low-res ORTEP in that paper (which is probably non-free and probably not fair-use) if that would be nicer for the hook. DMacks (talk) 20:22, 5 October 2014 (UTC)

Well, putting in the work and generating great graphics for us is always a solution! I think this is actually compound 1 from the figure (R1=R2=H) but that's right because that's the compound that they mention a theoretical calculation for (vs. a measured exchange rate of 1.6 MHz). Logically, since the computation is based on the moment of inertia of the phenylene, putting tert-butyls on it should have no effect on the figure. The main thing I'd want to see added to the figure (and admittedly, seems like a hassle) is a simple green looping "3D" arrow giving the indication of rotation, going around the phenylene group to indicate that's the part that rotates. Wnt (talk) 20:38, 6 October 2014 (UTC)

Compound 3 (m-methoxy) is the only one that has X-ray data in that article. But if you want just the color-coded skeletal diagram, it's trivial to have tert-butyl, or H, or whatever else. I uploaded a new revision at File:Molecular gyroscope 2007 uncaged.png that includes the green arrow for the phenylene rotation. Is that a good size and alignment compared to the structure itself? I think the article's table would benefit from a column with the rotation speed (that's probably one of the key gyroscopic parameters in addition to the structure definition itself?). To save space, the "reference" could be merged into the "pub year" column. DMacks (talk) 22:42, 6 October 2014 (UTC)

There is also an opportunity to write and add an article for Revolutions per second (has always redirected to RPM) ~ R.T.G 23:04, 7 October 2014 (UTC)

ALT2 ... that thermal energy at room temperature can spin a molecular gyroscope (pictured) at more than 2,400,000,000,000 times a second?

Sorry, I'm still not 100% sure unless you can point out where in a source in the article now does it say the stuff about thermal energy and room temp (presumably about 300 K). Otherwise I like Wnt's hook and would be fine with it. Jinkinson talk to me 12:54, 5 October 2014 (UTC)

Well I've posted on the reference desk and the first response back showed it wasn't one trillion, but 2.4 trillion, as it says 2.4 x 10¹². (Hook adjusted accordingly) Rest is still unresolved, ~ R.T.G 17:41, 5 October 2014 (UTC)

I am pretty sure it says heated between 245 and 281K. Google says that is -18 to 46 fahrenheit and -28 to 8 celsius. ~ R.T.G 13:04, 7 October 2014 (UTC)

ALT3 ... that a molecular gyroscope (pictured) can spin at 2,400,000,000,000 times a second?
ALT4 ... that a molecular gyroscope (pictured) can spin at 2,400,000,000,000 times a second at temperatures between 245 and 281 Kelvins?
ALT5 ... that a molecular gyroscope (pictured) can spin at 144,000,000,000,000 times a minute?
ALT6 ... that a molecular gyroscope (pictured) can spin at 144,000,000,000,000 RPM at temperatures between 245 and 281 Kelvins?
ALT7 ... that a molecular gyroscope (pictured) can spin at 144,000,000,000,000 RPM? <- new alts. I am fairly sure that's the temperature range in the citation. It doesn't actually say if or what temperature is specific to the 2.4t rps, but I thought it might be catchy as a hook so for the sake of seeing the alternatives, +maybe RPMs ~ R.T.G 22:57, 7 October 2014 (UTC)

Alt3 looks

good to go. Jinkinson talk to me 18:46, 10 October 2014 (UTC)