Talk:Table of nuclides/Archive 1
Old business
[edit]Graphic
[edit]Surely a picture is needed here Biddlesby 09:34, 18 June 2007 (UTC)
Comparison with Periodic Table
[edit]The comparison with the periodic table in the introduction: "This system of ordering nuclides can offer a greater insight into the characteristics of elements and isotopes than the more well known periodic table." suggests too much of a competition between the two. I suggest a more comparative approach, emphasizing that they cover two different bodies of data; e.g.
The chart of the nuclides illustrates nucleon structure much as the periodic table illustrates electron structure.
JohnAspinall 14:31, 31 August 2007 (UTC)
Map of the Nuclides
[edit]The lanl.gov Map of the Nuclides compares favorably in showing the interelationship of the stable isotopes with each other without other confusing details.WFPMWFPM (talk) 15:15, 9 September 2008 (UTC)
The NuclideMap graphic is almost useless. If enlarged enough to see what's written in the boxes, the resolution is so bad it's unreadable. If not enlarged, it's so small it's unreadable. Surely there is a suitable image somewhere with readable information.Saintonge235 (talk) 09:00, 12 March 2012 (UTC)
Merge with Isotope table (complete)
[edit]Why is this article separate from Isotope table (complete)?
JohnAspinall 14:31, 31 August 2007 (UTC)
Fair use rationale for Image:Chartofthenuclides cover.jpg
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BetacommandBot 07:30, 27 October 2007 (UTC)
Welcome to the new centralized talk place
[edit]Moving around articles is coming to an end. For the merge discussion see Talk:Table of nuclides/archive (complete). --Quilbert (talk) 01:46, 27 February 2008 (UTC)
Let me step on in here…
[edit]Holy smokes… talk about “doing the heavy lifting” Quilbert! You’ve addressed so many shortcomings with your solution. Now there is only one place to edit data, one venue to discuss issues, and multiple presentations of the data to serve every conceivable need. Well done. I’m sure the single discussion venue will take a bit of getting used to. I recently spent some time at Wikipedia talk:Manual of Style (dates and numbers) (I lead the Section-1 proposal). With only a bit of effort, topics can be well organized, like on Talk:MOSNUM. Greg L (my talk) 02:01, 27 February 2008 (UTC)
And thank you for your helpful input JWB. You have been the good shepherd of these pages for a long time, have obviously invested a great deal of effort into them, and are exceptionally knowledgeable on the subject. Unfortunately we seem to have managed to severely trample each others’ toes heading into these changes. Fortunately, Quilbert saw fit to jump in here before we broke our keyboards ;-). I hope we can treat what Quilbert has given us as a jumping point for a new beginning. Greg L (my talk) 02:21, 27 February 2008 (UTC)
Wow! Impressive that Quilbert did with those templates! Also, nice idea to merge the talk pages also. Not seen that done before! Congrats! --Rebroad (talk) 11:16, 5 March 2008 (UTC)
Vertical vs. Horizontal
[edit]In this text:
- Isotopes - Nuclides that neighbor each other horizontally; nuclides that have the same number of protons, or all of the same chemical element. Example: Carbon-13 and Carbon-14
- Isotones - Nuclides that neighbor each other vertically; nuclides that have the same number of neutrons. Example: Carbon-12 and Boron-11.
- Isobars - Nuclides that neighbor each other up-and-to-the-left and down-and-to-the-right; nuclides that have the same mass number. Example: Carbon-12 and Boron-12.
…shouldn’t the “horizontally” and “vertically” be swapped? When I think of these terms, I think of them with a mental picture of the tables on Table of nuclides (combined) and Table of nuclides (segmented, narrow) (example shown below). Aren’t the isotones neighboring each other horizontally in these tables? Is there some other table layout to which “horizontal” and “vertical” are referenced to, and if so, should they be? Greg L (my talk) 05:21, 27 February 2008 (UTC)
Z → | 0 | 1 | 2 | 3 | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
n ↓ | n | H | He | Li | 4 | 5 | |||||||||
0 | 1H | Be | B | 6 | 7 | ||||||||||
1 | 1n | 2H | 3He | 4Li | C | N | 8 | ||||||||
2 | 3H | 4He | 5Li | 6Be | 7B | 8C | 9N | O | 9 | ||||||
3 | 4H | 5He | 6Li | 7Be | 8B | 9C | 10N | 11O | F | 10 | |||||
4 | 5H | 6He | 7Li | 8Be | 9B | 10C | 11N
|
12O | 13F | Ne | 11 | 12 | |||
5 | 6H | 7He | 8Li | 9Be | 10B | 11C | 12N | 13O | 14F | 15Ne | Na | Mg | |||
6 | 7H | 8He | 9Li | 10Be | 11B | 12C | 13N | 14O | 15F | 16Ne | 17Na | 18Mg | 13 | 14 | |
7 | 9He | 10Li
|
11Be | 12B | 13C | 14N | 15O | 16F | 17Ne | 18Na | 19Mg | Al | Si | ||
8 | 10He | 11Li | 12Be | 13B | 14C | 15N | 16O | 17F | 18Ne | 19Na | 20Mg | 21Al | 22Si | ||
9 | 12Li | 13Be | 14B | 15C | 16N | 17O | 18F
|
19Ne | 20Na | 21Mg | 22Al | 23Si | |||
10 | 13Li | 14Be | 15B | 16C | 17N | 18O | 19F | 20Ne | 21Na | 22Mg | 23Al
|
24Si | |||
11 | 15Be | 16B | 17C | 18N | 19O | 20F | 21Ne | 22Na
|
23Mg | 24Al
|
25Si | ||||
12 | 16Be | 17B | 18C | 19N | 20O | 21F | 22Ne | 23Na | 24Mg | 25Al | 26Si | ||||
13 | 18B | 19C | 20N | 21O | 22F | 23Ne | 24Na
|
25Mg | 26Al
|
27Si | |||||
14 | 19B | 20C | 21N | 22O | 23F | 24Ne | 25Na | 26Mg | 27Al | 28Si | |||||
15 | 20B | 22N | 23O | 24F | 25Ne | 26Na | 27Mg | 28Al | 29Si | ||||||
16 | 21B | 22C | 23N | 24O | 25F | 26Ne | 27Na | 28Mg | 29Al | 30Si | |||||
17 | 25O | 26F | 27Ne | 28Na | 29Mg | 30Al | 31Si | ||||||||
18 | 26O | 27F | 28Ne | 29Na | 30Mg | 31Al | 32Si | ||||||||
19 | 27O | 28F | 29Ne | 30Na | 31Mg | 32Al
|
33Si | ||||||||
20 | 28O | 29F | 30Ne | 31Na | 32Mg | 33Al | 34Si | ||||||||
21 | 30F | 31Ne | 32Na | 33Mg | 34Al | 35Si | |||||||||
22 | 31F | 32Ne | 33Na | 34Mg | 35Al | 36Si | |||||||||
23 | 34Na | 35Mg | 36Al | 37Si | |||||||||||
24 | 34Ne | 35Na | 36Mg | 37Al | 38Si | ||||||||||
25 | 37Mg | 38Al | 39Si | ||||||||||||
26 | 37Na | 38Mg | 39Al | 40Si | |||||||||||
27 | 40Al | 41Si | |||||||||||||
28 | 39Na | 40Mg | 41Al | 42Si | |||||||||||
29 | 42Al | 43Si | |||||||||||||
30 | 43Al | 44Si | |||||||||||||
31 |
- You are right, I changed it to fit our layout. Most charts outside WP are rotated by 90 degrees counterclockwise. But that is impractical here, because in the upper left corner you would just see a void. --Quilbert (talk) 12:43, 27 February 2008 (UTC)
drip lines
[edit]Would in be possible to add the drip lines, say by a heavy cell border, in those case we know where it exists? kwami (talk) 07:30, 8 April 2008 (UTC)
- I have added support for drip lines, see Template talk:Iso1#Adding a drip line. --Quilbert (talk) 07:28, 14 April 2008 (UTC)
- Great! So why aren't there any in the table? I don't know myself which have been established.
- Okay, I see now we still don't know much. I thought maybe things had changed in the past decade or so. kwami (talk) 07:41, 14 April 2008 (UTC)
post-expand include size
[edit]I just noticed that the post-expand include size of Table of nuclides (combined) is near-critical:
<!-- NewPP limit report Preprocessor node count: 439487/1000000 Post-expand include size: 1958134/2048000 bytes Template argument size: 29208/2048000 bytes Expensive parser function count: 0/500 -->
See also Wikipedia:Template limits. Please help to watch this limit. We might have to change something when more nuclides are added. As of bug 13260 this might or might not be done by a simple change in Template:Isotones. --Quilbert (talk) 13:24, 21 May 2008 (UTC)
A = 3Z - an even number
[edit]The Table of nuclides has information on 4 different categories of nuclides. The even Z elements have the two categories EE and EO With the EE (even p, even n) having more than 1/2 of all the stable nuclides and the EO only about 1/6. The odd Z elements have the OE with approximately 1/6 and the OO categories with the OO only having only 4 stable plus 4 long lives unstable elements. Stability trend lines that cross elements must necessarily run through the EE+OE nuclides and have the formula A = 3Z - an even number. A = 3Z - 32 runs from 4294Mo to 57139La. A = 3Z - 38 runs from 68166Er to 82208Pb. In these areas the stable accumulation preference is to add an increment of 1 deuteron+1 extra neutron to maintain stability. The p verses n table of nuclides chart is unable to display these trend lines. A chart that can plots p (horizontal) verses the value A = 2Z (the excess neutron number) vertical. See Talk:Nuclear model ---WFPM (talk) 22:23, 28 May 2008 (UTC)
- I've actually prototyped some charts with this kind of skew. Please take a look at User:JWB#Skewed nuclide charts. On the skew 2 chart, you can see the vertical 68166Er to 82208Pb line. (in fact it extends all the way from 100Pd to 250Cm for the >1day nuclides visible on the chart) --JWB (talk) 22:42, 28 May 2008 (UTC)
The chart is not so much a "skewed" chart as it is a chart based on the hypothesis that the structure of the nucleus consists of a certain number of accumulated deuterons (as represented by the Z number) plus a certain number of "excess neutrons" (as represented by the A-2Z ordinate number}, which are added to the surface of the basic accumulated deuteron structure. The real physical models shown at Talk:Nuclear model are constructed based on that same hypothesis.WFPMWFPM (talk) 03:21, 7 June 2008 (UTC)
If you think about the stability trend line formula (A = 3Z - an even number) You note that the general stability tendency increases by 3 nucleons per element. If the increase is sequentially proton + neutron +?, we then note that most elements are stable with an excess of neutrons, so the sequence will be neutron + proton + neutron. And since the category of isotope that is most stable are the EE isotopes (with even numbers of both neutrons and protons) we might guess that where the increase is not 3 nucleons per element the accumulation sequence would continue to be + neutron + neutron through the area of stability. And eventually we get into the category of nuclides with too many extra neutrons, and which then are then changed into protons by the beta emission process.WFPM (talk) 01:59, 15 March 2010 (UTC)See User:JWB/Nuclide chart with skew 1
In the area of the table where additional stable or long lived isotopes might be encountered the 2 stability trend lines A = 3Z - 38 and A = 3Z - 40 are most prominent, with the A = 3Z-38 line covering the greatest range of the isotopes.WFPM (talk) 18:50, 20 March 2011 (UTC)
Finer halflife categories
[edit]For a long time I've thought it would be nice for the halflife shading to indicate something more precise than "100 days to 10000 years". Also, currently the colors are specified by single letters that are abbreviations for color names instead of halflife categories; except since someone shuffled the colors, they no longer match the actual colors.
I propose we use the digits 0-9 to indicate the range of 10x to 10x+1 years; for example 0 would mean 1 year to 10 years, and 9 would mean 1 billion to 10 billion years; however I'd like to stretch the 9 category a bit to include 232Th with halflife 14 billion years, so as to put it with the other nuclear fuels.
The current short-lived categories would remain the same for now, except that 100 days to 10 years (G) would be truncated to 100 days to 1 year, losing 29 of its 63 members. 1 to 10 days (V) would still have 130 members and 10 to 100 days (B) would still have 93 members. 21 super long lived primordial isotopes (O) would remain the same, as would the stable isotopes (R). Only the (Y) category would disappear completely.
Total number of nuclide macros changing from letter to number codes would be 105. --JWB (talk) 21:35, 2 September 2008 (UTC)
Log second nuclear halflives
[edit]Actinides[1] by decay chain | Half-life range (a) |
Fission products of 235U by yield[2] | ||||||
---|---|---|---|---|---|---|---|---|
4n | 4n + 1 | 4n + 2 | 4n + 3 | 4.5–7% | 0.04–1.25% | <0.001% | ||
228Ra№ | 4–6 a | 155Euþ | ||||||
248Bk[3] | > 9 a | |||||||
244Cmƒ | 241Puƒ | 250Cf | 227Ac№ | 10–29 a | 90Sr | 85Kr | 113mCdþ | |
232Uƒ | 238Puƒ | 243Cmƒ | 29–97 a | 137Cs | 151Smþ | 121mSn | ||
249Cfƒ | 242mAmƒ | 141–351 a |
No fission products have a half-life | |||||
241Amƒ | 251Cfƒ[4] | 430–900 a | ||||||
226Ra№ | 247Bk | 1.3–1.6 ka | ||||||
240Pu | 229Th | 246Cmƒ | 243Amƒ | 4.7–7.4 ka | ||||
245Cmƒ | 250Cm | 8.3–8.5 ka | ||||||
239Puƒ | 24.1 ka | |||||||
230Th№ | 231Pa№ | 32–76 ka | ||||||
236Npƒ | 233Uƒ | 234U№ | 150–250 ka | 99Tc₡ | 126Sn | |||
248Cm | 242Pu | 327–375 ka | 79Se₡ | |||||
1.53 Ma | 93Zr | |||||||
237Npƒ | 2.1–6.5 Ma | 135Cs₡ | 107Pd | |||||
236U | 247Cmƒ | 15–24 Ma | 129I₡ | |||||
244Pu | 80 Ma |
... nor beyond 15.7 Ma[5] | ||||||
232Th№ | 238U№ | 235Uƒ№ | 0.7–14.1 Ga | |||||
|
The best way to standardize the halflife decay values is to also show the value of the log to the base 10 of the halflife in seconds. Then you have a value that can be comparatively plotted on a chart. The range of the chart can be from any short time you like up to the log second lifetime of the universe. How about a range of 0 (1 second) to 18 (10E10.5years)?WFPM (talk) 20:06, 30 August 2009 (UTC)
- Powers of 10 of seconds don't have an obvious relationship to years, for those who can't quickly do division by 36 million in their heads. All discussions of long-lived isotopes take place in years, and changing from that terminology will make the halflife categories useless. For halflives greater than a year, we should use categories which are powers of 10 of years as I've already implemented in the Iso1 macro, but not converted the whole Table of Nuclides to yet. The table of actinides and fission products at right is an example of using the powers of 10 of years scheme.
- Any chart by log of halflife should be generated from more exact data than the rough brackets here. --JWB (talk) 20:51, 30 August 2009 (UTC)
- After you learn that a year is very nearly 10E7.5 seconds it isn't hard for interested persons to mentally figure the range of years they're dealing with by merely subtracting 7.5 from the exponent, and it's nice to have a number you can use on an ordinate chart.WFPM (talk) 01:35, 31 August 2009 (UTC)
- I rest my case on the math issue. I will be glad to help with the chart if you have any interest in actually doing that project. The number of nuclides per bracket decreases as the halflife increases, so we are talking about sorting out a relatively small number of nuclides at the long-halflife end. Also, you can simply make the log-time axis brackets of unequal size.
- After you learn that a year is very nearly 10E7.5 seconds it isn't hard for interested persons to mentally figure the range of years they're dealing with by merely subtracting 7.5 from the exponent, and it's nice to have a number you can use on an ordinate chart.WFPM (talk) 01:35, 31 August 2009 (UTC)
- If we had to settle on powers of 10 of a fixed time unit for some reason, decimal subdivisions of years would make more sense than huge multiples of seconds. --JWB (talk) 01:50, 31 August 2009 (UTC)
- Well I had to have a standard notation of halftime values, (greater than 1 second) so I went through the 74th CRC handbook and converted everything to log second halflife values for use in graph comparison purposes and it worked out pretty well. But I guess your application is different. Just a suggestion, and I was hoping not to have to do that all the time.WFPM (talk) 02:18, 31 August 2009 (UTC)
- If we have a table of halflives, it can be automatically converted into different formats by programs. If you want to make charts using this kind of data, I can help - I've done some SVG graphics.
- Well I had to have a standard notation of halftime values, (greater than 1 second) so I went through the 74th CRC handbook and converted everything to log second halflife values for use in graph comparison purposes and it worked out pretty well. But I guess your application is different. Just a suggestion, and I was hoping not to have to do that all the time.WFPM (talk) 02:18, 31 August 2009 (UTC)
- Source material is different from results for presentation. For the latter we want what's comprehensible quickly to the reader, not what's convenient for further computation. --JWB (talk) 02:27, 31 August 2009 (UTC)
- But when you're trying to evaluate multiple time values, it's nice to have everything be related to the same base unit. For example, I was comparing the reported halflives of 47Ag by graphing, and everything more or less fitted into the chart, except OO47Ag114, which was way too low, and popped up that way on the graph. So what about 47Ag114? I dont know. But it's a good question.WFPM (talk) 03:03, 31 August 2009 (UTC)
- Yes, it is nice for computation. Unfortunately, we do not have a metric system for time and people are not familiar with reckoning in all-decimal time units, so real-world presentation today has to stick to the customary units or become unreadable and irrelevant. And as you note, a mistake transforming one unit into another is large enough to catch by inspection. --JWB (talk) 03:24, 31 August 2009 (UTC)
- But when you're trying to evaluate multiple time values, it's nice to have everything be related to the same base unit. For example, I was comparing the reported halflives of 47Ag by graphing, and everything more or less fitted into the chart, except OO47Ag114, which was way too low, and popped up that way on the graph. So what about 47Ag114? I dont know. But it's a good question.WFPM (talk) 03:03, 31 August 2009 (UTC)
- Well I dont think you're ever going to get the public at large well enough informed about time to where they understand the subdivisions of time intervals. (Zeno wrote his paradox about that} But you would think that maybe Nubase would give the matter some thought for the sake of scientific clarity. I appreciate your problem and I very much admired the way that Isaac Asimov was able to communicate such subject matter in his scientific articles.WFPM (talk) 04:11, 31 August 2009 (UTC)
- This has been a good discussion. I am genuinely interested in seeing your data and making an SVG graphic from it. --JWB (talk) 05:07, 31 August 2009 (UTC)
- Well I dont think you're ever going to get the public at large well enough informed about time to where they understand the subdivisions of time intervals. (Zeno wrote his paradox about that} But you would think that maybe Nubase would give the matter some thought for the sake of scientific clarity. I appreciate your problem and I very much admired the way that Isaac Asimov was able to communicate such subject matter in his scientific articles.WFPM (talk) 04:11, 31 August 2009 (UTC)
- You might note that Nubase was evidently aware that the subdivision of nuclides by element was an arbitrary decision not related to the creation process, and that they subdivided by atomic mass values. But I think that their calculation of relative stability values was related to the Semiemperical Binding energy formula which does take into consideration nuclide interrelationships, including the "extra neutron value" A-2Z.WFPM (talk) 20:56, 31 August 2009 (UTC)
Too many white-shaded boxes
[edit]More than half of all isotopes apparently fall into the white-coloured "<1 day" category, including practically all transactinides. To make the colouring more useful, I would suggest splitting this category in two (e.g. smaller or larger than 1s / 10s / 1min). Instead, one could e.g. merge the "1-10 day" and "10-100 days" categories to be the same colour (the two are the finest categories at the moment, spanning only one power of 10 each). Regards --Roentgenium111 (talk) 16:56, 11 April 2010 (UTC)
- Sure, I also vote you go ahead. The splits in time for ordering are arbitrary anyway, and thus should be done aesthetically to make roughly equal "chunks" or block of nuclides, and also whenever we find that any chemical class or production-class of nuclides (like the transactinides) happens to fit into a convenient human log-time slot. For example isotopes used as radiotracers in biomedical apps can't have lives less than about 10 seconds, and 2 hours to about 10 days is preferred. SBHarris 11:45, 3 January 2012 (UTC)
Problem with key in Table of nuclides (complete)
[edit]As pointed out by someone in the old talk page, a color for the half-life interval from 103Ma to 700Ma is missing in the key. And boxes with variously coloured borders are not explained there in the key. And for the n-number on the left, the number 45 is repeated. Can someone rectify this (I don't know how)? Thanks.Kpufferfish (talk) 01:40, 20 March 2010 (UTC)
- Uh... I copied the key from Table of nuclides (combined), which explains the border colour (sort of). But it still lacks a color for the half-life interval from 103Ma to 700Ma.Kpufferfish (talk) 01:40, 20 March 2010 (UTC)
drip lines
[edit]I obviously don't understand s.t., but if drip lines limit the range of nuclides, why do we plot nuclides beyond the drip lines? kwami (talk) 04:51, 31 August 2009 (UTC)
- Beyond the drip lines, nuclides decay by neutron or proton emission, but they still exist, albeit with short halflives. In some cases they may have longer halflives than some nuclides within the drip lines that decay by beta decay or other mechanisms. --JWB (talk) 05:05, 31 August 2009 (UTC)
- Ah, I understand now. So the orange in the published chart are isotopes beyond the p drip line, whereas the unlabeled violet is beyond the n drip line. kwami (talk) 19:23, 31 August 2009 (UTC)
tungsten
[edit]Shouldn't W be purple, as it's not thought to be completely stable? The published chart at the top of this page d n list any isotope as stable. kwami (talk) 05:11, 31 August 2009 (UTC)
- Isotopes of tungsten gives halflife lower limits for 4 isotopes while still listing them as STABLE. I think this means they have not been found to be radioactive so far, but that there are theoretical reasons why alpha decay might be possible, and they might in the future to be found to be radioactive with even longer halflives than the current limits, which are already on the order of billions times the age of the universe. --JWB (talk) 16:29, 31 August 2009 (UTC)
- Yes, as 'currently not known to be unstable', it makes sense. I just thought it was odd that the published chart at the top of the page lists tungsten as unstable but bismuth as stable, while we have just the opposite. Maybe we should have a note explaining that? kwami (talk) 19:19, 31 August 2009 (UTC)
- See List of nuclides for a discussion of the stability problem. All elements with Z > 40 (niobium and up) are theoretically (energetically) unstable to spontaneous fission, and others to double beta-decay. But for many (about 137) of these, the process has never been observed. For others (about 30 nuclides), the predicted process has been observed at the correct energy, but so rarely that a half-life cannot be determined, but only a lower bound set. Sometimes these lower bounds come from observation (like the lower bound for decay of the proton) or other times from theory (there is good theory for alpha decay in terms of relating half life to decay energy-- see Geiger-Nuttall law). In both cases, if a half life is not known to precission, the nuclide is classed as "stable." In one or two cases, a half life is known by measurement of decay products in rocks, and these radioisotopes also are classed as unstable, since the number is known. The longest lived radionuclide, Te-130, has the distinction of having its half life known in this way.
To boil this down, if we didn't class "theoretically unstable" nuclides as "stable", the list of stable nuclides would only be 90 nuclides. If you take the strict criterion that half life must be known, you get up to 257 nuclides. If you take out the 30 nuclides for which decay has been seen, but half life isn't known, you go down to 227 nuclides. I've made up a handy table to that effect in list of nuclides. It's not absolutely accurate (elements like bismuth and nuclides like W-180 change year to year) but it's pretty close. SBHarris 23:14, 2 October 2010 (UTC)
- I didn't know any of that. However, if decay has actually been observed, it seems quite odd to me to continue to call the nuclide "stable". Perhaps we should make that clear? — kwami (talk) 00:43, 3 October 2010 (UTC)
- It is made clear in list of nuclides, where the decays are noted. It's not so clear in the table here. This bothered me in the past, too, when I thought nuclides were either stable, or not, and no in between. But you have to get used to the fact that only the first 40 elements have an isotope that is totally stable, and all the rest are mildly radioactive. VERY mildly. Since in quantum mechanics, anything that CAN happen energetically, eventually DOES happen. And if protons decay, all elements are slightly radioactive. SBHarris 00:55, 3 October 2010 (UTC)
- There's a huge difference between such Heisenberg effects and what we're talking about here though, isn't there? (I mean, that would apply to the lower 40 too.) And of course it's quite possible we haven't seen protons decay because they don't. But yeah, interesting that from 41 on up, all are at least potentially very slightly unstable. Wonder how long it will take us to figure out if they are. — kwami (talk) 03:16, 3 October 2010 (UTC)
- Well, ultimately, alpha decay, cluster decay, and spontaneous fission, are all due to quantum tunnelling. I suppose that all elements heavier than Fe and Ni are energetically able to decay to those plus smaller fragments, but for nuclei smaller than Nb (41) but larger than Ni (28), this requires fission into 3 daughters, not 2. With that little energy to work with, that's extremely unlikely. So it's possible, but many, many orders of magnitude less likely. Above Z = 40 is where nuclei can no longer be built symmetrically from two identical stable daughters (eg, 2 calcium-40's). That means that above Z= 40, fission has to be assymetrical also, if the daughters are to have anything like decent binding energies per nucleon. This also hurts the chances of it happening. SBHarris 20:18, 3 October 2010 (UTC)
- There's a huge difference between such Heisenberg effects and what we're talking about here though, isn't there? (I mean, that would apply to the lower 40 too.) And of course it's quite possible we haven't seen protons decay because they don't. But yeah, interesting that from 41 on up, all are at least potentially very slightly unstable. Wonder how long it will take us to figure out if they are. — kwami (talk) 03:16, 3 October 2010 (UTC)
- It is made clear in list of nuclides, where the decays are noted. It's not so clear in the table here. This bothered me in the past, too, when I thought nuclides were either stable, or not, and no in between. But you have to get used to the fact that only the first 40 elements have an isotope that is totally stable, and all the rest are mildly radioactive. VERY mildly. Since in quantum mechanics, anything that CAN happen energetically, eventually DOES happen. And if protons decay, all elements are slightly radioactive. SBHarris 00:55, 3 October 2010 (UTC)
- I didn't know any of that. However, if decay has actually been observed, it seems quite odd to me to continue to call the nuclide "stable". Perhaps we should make that clear? — kwami (talk) 00:43, 3 October 2010 (UTC)
- See List of nuclides for a discussion of the stability problem. All elements with Z > 40 (niobium and up) are theoretically (energetically) unstable to spontaneous fission, and others to double beta-decay. But for many (about 137) of these, the process has never been observed. For others (about 30 nuclides), the predicted process has been observed at the correct energy, but so rarely that a half-life cannot be determined, but only a lower bound set. Sometimes these lower bounds come from observation (like the lower bound for decay of the proton) or other times from theory (there is good theory for alpha decay in terms of relating half life to decay energy-- see Geiger-Nuttall law). In both cases, if a half life is not known to precission, the nuclide is classed as "stable." In one or two cases, a half life is known by measurement of decay products in rocks, and these radioisotopes also are classed as unstable, since the number is known. The longest lived radionuclide, Te-130, has the distinction of having its half life known in this way.
- Yes, as 'currently not known to be unstable', it makes sense. I just thought it was odd that the published chart at the top of the page lists tungsten as unstable but bismuth as stable, while we have just the opposite. Maybe we should have a note explaining that? kwami (talk) 19:19, 31 August 2009 (UTC)
Overall element information
[edit]- Let's just say that each element to be understood needs a chart of halflife plus percentage occurrence values over the entire isotopic spectrum in order to understand the relationship of the stable isotopes to rest of the isotopes of that element. Then comes the problem of establishing the relationship of the element to its neighboring elements in the manner best indicating nature's process of creation (by accumulation) of these elemental atoms. And it is doubtfull that their chemical properties had anything to do with the process. I suggest that you look at the image of the Whirlpool Galaxy and consider what atomic creation processes were going on there about 25,000,000 years ago. And it's a nearby galaxy, so to speak, relative to the size of the universe.WFPM (talk) 19:06, 31 August 2009 (UTC)
New template with html table of nuclides.
[edit]I've created a new highly customizable template at Template:Nuclides.
Its not completely finished but it does have all the stable nuclei.
If anyone has any questions or suggestions feel free to respond here or on the template talk page.
Just granpa (talk) 04:11, 28 September 2010 (UTC)
0 | 2 | 4 | 6 | 8 | 1 0 |
2 | 4 | 6 | 8 | 2 0 |
2 | 4 | 6 | 8 | 3 0 |
2 | 4 | 6 | 8 | 4 0 |
2 | 4 | 6 | 8 | 5 0
| ||||||||||||||||||||||||||||||||||||||
0 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
He | 2 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Be | 4 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
C | 6 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
O | 8 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ne | 10 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Mg | 12 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Si | 14 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
S | 16 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ar | 18 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ca | 20 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ti | 22 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cr | 24 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Fe | 26 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ni | 28 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Zn | 30 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ge | 32 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Se | 34 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Kr | 36 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Sr | 38 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Zr | 40 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Mo | 42 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ru | 44 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pd | 46 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cd | 48 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Sn | 50 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Te | 52 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Xe | 54 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ba | 56 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ce | 58 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Nd | 60 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Sm | 62 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Gd | 64 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Dy | 66 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Er | 68 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Yb | 70 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Hf | 72 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
W | 74 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Os | 76 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pt | 78 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Hg | 80 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pb | 82 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Po | 84 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Rn | 86 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ra | 88 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Th | 90 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
U | 92 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pu | 94 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cm | 96 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cf | 98 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
0 | 2 | 4 | 6 | 8 | 1 0 |
2 | 4 | 6 | 8 | 2 0 |
2 | 4 | 6 | 8 | 3 0 |
2 | 4 | 6 | 8 | 4 0 |
2 | 4 | 6 | 8 | 5 0 |
2 | 4 | 6 | 8 | ||||||||||||||||||||||||||||||||||
|
_ | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 |
| |||||||||||||||||||||||||||||||||||||
H | 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Li | 3 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
B | 5 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
N | 7 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
F | 9 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Na | 11 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Al | 13 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
P | 15 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cl | 17 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
K | 19 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Sc | 21 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
V | 23 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Mn | 25 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Co | 27 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cu | 29 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ga | 31 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
As | 33 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Br | 35 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Rb | 37 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Y | 39 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Nb | 41 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Tc | 43 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Rh | 45 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ag | 47 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
In | 49 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Sb | 51 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
I | 53 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cs | 55 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
La | 57 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pr | 59 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pm | 61 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Eu | 63 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Tb | 65 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ho | 67 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Tm | 69 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Lu | 71 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ta | 73 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Re | 75 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ir | 77 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Au | 79 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Tl | 81 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Bi | 83 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
At | 85 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Fr | 87 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ac | 89 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pa | 91 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Np | 93 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Am | 95 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Bk | 97 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Es | 99 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
_ | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | 1 | 3 | 5 | 7 | 9 | |||||||||||||||||||||||||||||||||
|
Suggest you compare this table with User:JWB/Nuclide chart with skew 1 to note similarities.WFPM (talk) 16:33, 17 March 2011 (UTC) Also note some discrepancies.
Remove He-2 (diproton)?
[edit]It has been suggested at Talk:Isotopes of helium that He-2 (the diproton) be removed from the table Table of nuclides (complete), because it is only a hypothetical entity which has never been observed, even with a short half-life. The discussion of the He-2 problem can be retained as a section of the Isotopes of helium article, but the tables would be restricted to nuclides known to actually exist.
Question 1: Do other editors agree? If not, why not?
Question 2: Does anyone know HOW to modify Table of nuclides (complete)? I cannot find the actual source code in order to remove He-2. Dirac66 (talk) 15:29, 27 July 2011 (UTC)
- I agree and boldly killed it. SBHarris 00:48, 28 July 2011 (UTC)
- The removal has messed up the table, but I don't know how to revert it (it seems to be encoded in a myriad of different templates which I have no idea how to find the template that was edited to delete diproton.) Whoop whoop pull up Bitching Betty | Averted crashes 01:58, 31 July 2011 (UTC)
- Yes, I see the problem. The third line of the table now has entries 0, space, 1H, Li, Be, 5, 6. It should be 0, space, 1H, space, Li, Be, 5, 6. SBHarris, since you seem to be the only one that knows where to locate the source code for this table, could you please insert the second space where 2He was, so that Li, Be, 5, 6 move to the correct columns? Or if there is a problem inserting a space, perhaps a placeholder such as a dash. Dirac66 (talk) 02:30, 31 July 2011 (UTC)
- OK, I have now succeeded in inserting the needed space in Template:Isotones to fix the table. Dirac66 (talk) 23:08, 7 August 2011 (UTC)
- Sorry, I just saw your note, or I would have responded before. I see you found the template and did it yourself. In future, put something on my TALK page, as I have something like 1300 pages on my watchlist, and miss a lot of stuff. SBHarris 23:36, 7 August 2011 (UTC)
- OK thanks. I finally found the template today by ... checking your list of contributions made just prior to your comment above. Dirac66 (talk) 00:24, 8 August 2011 (UTC)
- Sorry, I just saw your note, or I would have responded before. I see you found the template and did it yourself. In future, put something on my TALK page, as I have something like 1300 pages on my watchlist, and miss a lot of stuff. SBHarris 23:36, 7 August 2011 (UTC)
- OK, I have now succeeded in inserting the needed space in Template:Isotones to fix the table. Dirac66 (talk) 23:08, 7 August 2011 (UTC)
- Yes, I see the problem. The third line of the table now has entries 0, space, 1H, Li, Be, 5, 6. It should be 0, space, 1H, space, Li, Be, 5, 6. SBHarris, since you seem to be the only one that knows where to locate the source code for this table, could you please insert the second space where 2He was, so that Li, Be, 5, 6 move to the correct columns? Or if there is a problem inserting a space, perhaps a placeholder such as a dash. Dirac66 (talk) 02:30, 31 July 2011 (UTC)
- The removal has messed up the table, but I don't know how to revert it (it seems to be encoded in a myriad of different templates which I have no idea how to find the template that was edited to delete diproton.) Whoop whoop pull up Bitching Betty | Averted crashes 01:58, 31 July 2011 (UTC)
Potassium-40 article is not linked to.
[edit]Rather than figure things out I'm just going to point out that the Potassium_40 article is not linked to from the Table_of_nuclides_(complete) article, like the Oxygen_18 article is, for example . Dave3457 (talk) 13:52, 29 August 2011 (UTC)
- OK, I went into Template:Isotones and linked to the K-40 article since you mentioned it. However most of the nuclides in the table are not linked to articles, and I don't really think it is important to link them all, which would take quite a bit of work. Dirac66 (talk) 18:01, 29 August 2011 (UTC)
- Thanks Dirac. Actually, your link to the Potassium 40 article is different then the link to the Oxygen 18 article and others. The Oxygen 18 link, links the number 18, you linked the symbol. Refer...(Table_of_nuclides_(complete)). Personally, what would be ideal, for all of them, is if both the number and symbol were linked, but that's not going to happen. I checked and I'm pretty sure that Potassium 40 was an oversight. I checked the Radioactive_isotope article and of the 14 mentioned in a list, the 5 that had their own articles were linked to. Thanks again for your time. Dave3457 (talk) 08:18, 30 August 2011 (UTC)
- I have now linked K-40 via the number as for O-18 and the others which are linked. If you want to make more changes, what has to be edited is Template:Isotones. It's tricky to edit because you can't read the data in browsing mode. You have to go into edit mode and work with the source code, and cannot pre-visualize before saving. This is annoying and I don't know why the file is set up this way, but I don't know how to change it. Dirac66 (talk) 01:19, 1 September 2011 (UTC)
- Thanks Dirac. Actually, your link to the Potassium 40 article is different then the link to the Oxygen 18 article and others. The Oxygen 18 link, links the number 18, you linked the symbol. Refer...(Table_of_nuclides_(complete)). Personally, what would be ideal, for all of them, is if both the number and symbol were linked, but that's not going to happen. I checked and I'm pretty sure that Potassium 40 was an oversight. I checked the Radioactive_isotope article and of the 14 mentioned in a list, the 5 that had their own articles were linked to. Thanks again for your time. Dave3457 (talk) 08:18, 30 August 2011 (UTC)
Tantalum-180m
[edit]Just customized the page a little to reflect Ta-180m's observationally stable nature. All edits by 86.22.240.74; I forgot to log in. I also edited the key at the top. Elite6809 (talk) 16:53, 28 May 2012 (UTC)
Kr-78&Ta-180m
[edit]Why Kr-78 and Ta-180m are purple? Both of them should be gray! (Because they're "stable nuclide") — Preceding unsigned comment added by 59.126.202.81 (talk) 14:01, 14 July 2012 (UTC)
Kr-78
[edit]The nuclide "Kr-78" is stable! — Preceding unsigned comment added by 59.126.202.81 (talk) 15:25, 29 July 2012 (UTC)
Bi 210m
[edit]In the table of nuclides meta-stable Bi 210m is colored as unstable, however on the wikipedia page for Bismuth and Isotopes for Bismuth it says it has a half-life of millions of years and is by that account the second-longest lived nuclear isomer. I would change the color but am not sure how. — Preceding unsigned comment added by 216.128.146.3 (talk) 20:02, 17 April 2013 (UTC)
Row 45
[edit]Is there a special reason why row 45 has its number twice? -DePiep (talk) 14:00, 18 June 2013 (UTC)
- No: it shouldn't have its number twice. Double sharp (talk) 07:45, 11 September 2014 (UTC)
Color
[edit]Could it be helpful to add a new color after white? We have elements in the 110s lumped with elements which won't completely destroy themselves for as much as a week. My suggestion is to add a more reddish color somewhere in the last three colors (preferrably at the end to avoid shifting other colors up or down) for the many isotopes with half-lives of under a second. MissingUTAH (talk) 23:55, 25 December 2014 (UTC)
Switched axes
[edit]The image and description at the center of the article, under "Trends in the chart of nuclides" has the axes switched (i.e. is rotated by 90 degrees) relative to the image in the upper right corner (which is the standard representation, see below). This is very confusing. So when the description says that "isotopes neighbor each other vertically" they really neighbor each other horizontally in the standard chart using the Segre-arrangement.
To confirm that the familiar presentation with the stable elements extending from the lower left to the upper right is the standard one, I googled "Table of nuclides images" and found that indeed this representation accounts for 90% of the images coming up, with important laboratories both in the US (Brookhaven) and Europe (Karlsruhe) supporting it. It is very surprising that the "Available Representations" do not include the Brookhaven/Karlsruhe format.
The nonstandard presentation should be replaced with the standard one. If that's not possible, the differences between the two conventions need to be pointed out. Klaus Schmidt-Rohr (talk) 22:09, 30 December 2015 (UTC)
I was about to say the same thing, looks like you beat me to it. Well, the article on Radioactive decay also has it wrong, which is why I looked here. Gah4 (talk) 15:27, 3 June 2016 (UTC)
- Yes, and there are is another problem with the top right figure - if you will notice the blue and pink regions are switched in the upper and lower panels. There is a figure shown on many articles that has Z on abscissa and N on ordinate, which I believe is a non-standard representation for a Segre chart. I've recently put together a customized set of figures for the new article Valley of stability. Feel free to borrow from that article, relate this article to it as necessary, and contribute to that article. We should call these charts "Segre charts" - that is their name, it seems. Bdushaw (talk) 15:27, 14 July 2016 (UTC)
- ^ Plus radium (element 88). While actually a sub-actinide, it immediately precedes actinium (89) and follows a three-element gap of instability after polonium (84) where no nuclides have half-lives of at least four years (the longest-lived nuclide in the gap is radon-222 with a half life of less than four days). Radium's longest lived isotope, at 1,600 years, thus merits the element's inclusion here.
- ^ Specifically from thermal neutron fission of uranium-235, e.g. in a typical nuclear reactor.
- ^ Milsted, J.; Friedman, A. M.; Stevens, C. M. (1965). "The alpha half-life of berkelium-247; a new long-lived isomer of berkelium-248". Nuclear Physics. 71 (2): 299. Bibcode:1965NucPh..71..299M. doi:10.1016/0029-5582(65)90719-4.
"The isotopic analyses disclosed a species of mass 248 in constant abundance in three samples analysed over a period of about 10 months. This was ascribed to an isomer of Bk248 with a half-life greater than 9 [years]. No growth of Cf248 was detected, and a lower limit for the β− half-life can be set at about 104 [years]. No alpha activity attributable to the new isomer has been detected; the alpha half-life is probably greater than 300 [years]." - ^ This is the heaviest nuclide with a half-life of at least four years before the "sea of instability".
- ^ Excluding those "classically stable" nuclides with half-lives significantly in excess of 232Th; e.g., while 113mCd has a half-life of only fourteen years, that of 113Cd is eight quadrillion years.