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Good article Samarium has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can reassess it.
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Article changed over to new Wikipedia:WikiProject Elements format by schnee. Elementbox converted 11:14, 10 July 2005 by Femto (previous revision was that of 13:24, 9 July 2005).

Information Sources[edit]

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Samarium. Data for the table was obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units.


Note: Talk pertaining to the old version of the Samarium entry (prior to conversion to the new standard format) has been archived at Talk:Samarium/Archived.


There will be much to say about the element itself. There can be a separate topic on the chemistry and compounds of Samarium. Don't merge please ----

Question? How can you be sure there is no stable EE62SM146? It is unique in not being stable with only 2 additional neutrons above the lowest stable samarian isotope EE62SM144? All the other rare earth elements have stable isotopes in such a circumstance. And it's a long half life element, so why couldn't a portion of it be stable, And the article makes no mention of this irregularity. WFPMWFPM (talk) 00:37, 2 November 2008 (UTC)WFPM (talk) 21:52, 1 July 2009 (UTC)

These three articles have been tagged for their lack of notability - I suggest that they get 'merged' into this article. They are already mentioned by their chemical symbols in the compound section - I suggest with the addition of their names the 'merger' will be complete. Madmedea 15:53, 11 January 2007 (UTC)

  • Oppose. These three articles are samarium(III) fluoride, samarium(III) oxide and samarium(II) chloride. These compounds are not the same as samarium metal. They are indeed tagged long with the importance tag, but being tagged for long does not mean they are then ready to be removed/merged, whatever. I think the importance tag is the tag for these articles, they do not state any importance (just as the {{importance}} says, but will await a bit more discussion before reverting. --Dirk Beetstra T C 17:13, 11 January 2007 (UTC)
  • OpposeThey have been tagged simply because the tagger is unaware of the notability of the compounds, not that there isn't any. In fact, the US government tracks the price of Sm2O3 ($75/kg in 1997). These compounds have vastly different properties and uses, and while they should be mentioned on the main samarium page, they deserve separate treatment. Walkerma 18:31, 11 January 2007 (UTC)
  • Oppose This makes about as much sense as merging samarium(III) fluoride, samarium(III) oxide and samarium(II) chloride into the articles on their anions. Does sodium chloride belong in the sodium article? Obviously not. I'm going to remove the merge tags. --Calibas 19:45, 25 February 2007 (UTC)

Would anyone please enlighten me what is being proposed to merge ? Thank you indeed. Materialscientist (talk) 22:16, 1 July 2009 (UTC)

radioactive decay[edit]

Sm-149 (along with 146, 147, & 148) would decay by alpha emission, not beta decay (Eu-149 decays to Sm-149 by electron capture). Is there any reference for the decay of Sm-149? At least one isotope table lists it as stable. (talk) 07:35, 12 February 2011 (UTC)

I shall remove that info from the infobox, as I can't find reliable reference for alpha decay - [1] [2] [3] say it is stable. Materialscientist (talk) 07:51, 12 February 2011 (UTC)
The Isotopes section (& Isotopes of samarium entry) still describe Sm-149 as radioactive. (talk) 05:13, 13 February 2011 (UTC)
Thanks. "Corrected". My CRC copy lists it as alpha emitter (will check a newer version tomorrow). Confusing situation. The estimated lifetime is not unmeasurably long. Materialscientist (talk) 05:38, 13 February 2011 (UTC)
I remember seeing it listed as an alpha emitter once upon a time... Confusing indeed. (talk) 08:59, 13 February 2011 (UTC)

Assorted problems[edit]

  • Compounds - Sm - if the symmetry is rhombohedral shouldn't a=b=c? SmH3 - if the symmetry is cubic a=b=c.
  • Halides - there is no double bond in 1,2-diiodoethane.
  • Borides - "Increasing the temperature results in the preferential formation of Sm6" - presumably this should be SmB6.
  • Other inorganic compounds - Sn & Pb are not non-metallic (Ge & Sb are debatable).
  • Organometallic compounds - Sm(OR)Cl3 should be Sm(OR)3.
  • Isotopes - Sm-146 also has a half-life of (much) more than 2 days. If Sm-149 decays it (along with Sm-146, 147, & 148) would be by alpha emission.
  • Applications - "most of the fusion and decay products of samarium-149" should be "most of the neutron capture products of samarium".
Fixed all, stumbled here - that sentence meant to say that the "initial" Sm-149, after various capture and decay cycles in the reactor, would produce neutron-capturing isotopes. Materialscientist (talk) 04:02, 25 February 2011 (UTC)
  • Non-commercial applications - Samarium-neodymium dating would not use Sm-146, which does not occur in nature (except possibly in trace amounts). It presumably uses Sm-147 & Nd-143 (Sm-148 & Nd-144 should also work but would be less sensitive).

There are also some minor typos; is it worth listing them? (talk) 03:12, 25 February 2011 (UTC)

Yes, or just fix them directly. Materialscientist (talk) 04:02, 25 February 2011 (UTC)

OK, minor typos:

  • Physical properties - Applying higher pressure of the order OF hundreds or thousands OF kilobars...
  • Chemical properties - ...Sm(III) ions, which exist as (delete a) [Sm...
  • Applications - Radioactive samarium-153 is A beta emitter.. (talk) 08:44, 25 February 2011 (UTC)
    Fixed. Thanks a lot. Materialscientist (talk) 08:51, 25 February 2011 (UTC)
    SmH3 is still listed as cubic but c is not identical to a & b. (talk) 01:38, 26 February 2011 (UTC)
    Sorry, missed that. Materialscientist (talk) 03:13, 26 February 2011 (UTC)

GA Review[edit]

This review is transcluded from Talk:Samarium/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: FREYWA 09:54, 1 May 2011 (UTC)

Copper may be complete, but we have another review going on! This is samarium, and the test begins now!


GA review – see WP:WIAGA for criteria

  1. Is it reasonably well written?
    A. Prose quality:
    There are a lot of holes in the article, most of them in the history. "Reasonably pure element was created...", "Later Boisbaudran's samaria was transformed into samarium...", " was not until recent years that relatively pure samarium has been isolated through ion exchange processes...", and so on. FIX THEM!
    B. MoS compliance for lead, layout, words to watch, fiction, and lists:
    The lead and layout are fine, as is the fiction and lists, but what about the words to watch? There is a however in the lead section! Now, look for also's and however's in the body of the article and remove them (example: the borides section).
  2. Is it factually accurate and verifiable?
    A. References to sources:
    B. Citation of reliable sources where necessary:
    C. No original research:
  3. Is it broad in its coverage?
    A. Major aspects:
    B. Focused:
  4. Is it neutral?
    Fair representation without bias:
  5. Is it stable?
    No edit wars, etc:
  6. Does it contain images to illustrate the topic?
    A. Images are copyright tagged, and non-free images have fair use rationales:
    B. Images are provided where possible and appropriate, with suitable captions:
  7. Overall:
    Pass or Fail:


Recycling method for neodymium and samarium[edit]

Perhaps mention in article, see Recycling of neodymium and samarium KVDP (talk) 07:59, 1 June 2013 (UTC)

Strange sentence re halide structures[edit]

The following statement was ín the version that passed GA "...samarium halides change their crystal structures when one type of halide atoms is substituted for another, which is an uncommon behavior for most elements (e. g. actinides)." ???? Quickly looking at Wells, the structures of all the lanthanide halides change when the halide changes, even most of the actinides, which is simplistically is what would be expected. The statement is so obviously wrong that something else must surely have been intended, but I'm struggling to see what it is. Axiosaurus (talk) 09:39, 6 February 2014 (UTC)