User:Praseodymium-141/Samarium

From Wikipedia, the free encyclopedia

checkY = Certain. checkY = Probably.

Comments by Sandbh[edit]

1. Standard atomic weight Ar°(Sm) 150.36±0.02 150.36±0.02 (abridged)[1]

I do not understand the need for two entries for atomic weight nor the mention of "abridged". Citation 1 does not use this term.

2-5

2. checkY Both sources check out.

3. Checks out but mention of "SmB6-" should be to "SmB6-",  Fixed

4. checkY Correct.

5. The date of the source is shown as 1984 but is in fact 1983. The page number is shown as E110 but is in fact E-112. The units are shown as cm3/mol but in the reference are shown as cgs. The figure in reference is for a temperature of 291 K; this should be noted in the WP entry. The ISBN of 0-8493-0464-4 should be converted to 13-number format.  Fixed.

6. An entry for 145Sm is missing (half-life 340 days). The half-life for 146Sm does not check out; the source lists it as 68 My. There is no consistency in rounding of abundances and half-lives.

Removed

7. I could not find anything in the citation supporting the assertion that "Samarium has no significant biological role; some samarium salts are slightly toxic."

Removed.
7

7. The source says, "Samarium has no significant biological role".  Fixed

8. This source supports the listed boiling point of Sm. i do not understand why it is required since source 10 says the same thing.

9. This source is linked to the 81st (2000) edition of the CRC Handbook but the WP entry strangely says it is for the edition of "2004-06-29", whatever that means. The entry in the CRC Handbook does not support the WP statement that, "samarium is the third most volatile lanthanide after ytterbium and europium and comparable in this respect to lead and barium; this helps separation of samarium from its ores."

10. "Samarium is calculated to have one of the largest atomic radii of the elements; with a radius of 238 pm, only potassium, praseodymium, barium, rubidium and caesium are larger."

The citation only partly checks out. It only covers from He to Rn. Potassium, praseodymium, barium, rubidium and caesium are indeed larger. I note La and Ce have larger radii shown in parentheses. The paper does not explain what the parentheses mean.

I do not have access to the source. The reference is also used here, where La and Ce have smaller radii. I don't know though. 141Pr {contribs} 16:46, 30 May 2023 (UTC)

11. Is noted below and does not check out.

a b c d Shi, N.; Fort, D. (1985). "Preparation of samarium in the double hexagonal close packed form". Journal of the Less Common Metals. 113 (2): 21. doi:10.1016/0022-5088(85)90294-2.

Here:

a = a tetragonal phase appearing at about 900 kbar.
b = Thin films of samarium obtained by vapor deposition may contain the hcp or dhcp phases in ambient conditions.
c = trigonal samarium
d = hexagonal samarium

Item b is indeed mentioned by Shi & Fort. However they say nothing in support of a, c and d that I could see.

12-16

12. "The metal transforms to an antiferromagnetic state upon cooling to 14.8 K."

The article says, "it is believed [italics added] that these metals become anti-ferromagnetic below these temperatures." Since the article is from 1957 there is probably a more recent citations that would confirm this.

13. checkY Cited to support #12, above. Checks out.

14. "Individual samarium atoms can be isolated by encapsulating them into fullerene molecules."

checkY Correct.

15. "They can also be doped (intentional adding of samarium atoms) between the C60 molecules in the fullerene solid, rendering it superconductive at temperatures below 8 K."  Fixed

The source says at a temperature of 8 K, rather than at temperatures below 8 K. The WP sentence is badly constructed. It should say something like, "Samarium atoms can be intercalated into the interstices of bulk C60 to form a solid solution of nominal composition Sm3C60, which is superconducting at a temperature of 8 K.

16. "Samarium doping of iron-based superconductors – a class of high-temperature superconductor – increases their transition to normal conductivity temperature up to 56 K, the highest value achieved so far in this series."

checkY Correct.

17. "Samarium is quite electropositive and reacts slowly with cold water and rapidly with hot water to form samarium hydroxide:"

The citation is to Webelements. Retrieved 2009-06-06. A more reliable source is needed.

18

18. "Samarium dissolves readily in dilute sulfuric acid to form solutions containing the yellow..."

The citation is to "Greenwood", which refers to Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth–Heinemann. ISBN 0-08-037941-9. The citation should say, "c:.

The ISBN needs to be converted to 13 digit form.  Fixed

The citation does not check out; I could not find any reference in the source to samarium acting in this way.

Found in Greenwood & Earnshaw 1997 page p. 1243, saying that the Sm3+ is yellow in aqueous solutions. Doesn't explicitly say that sulfuric acid dissolves samarium metal, but considering that it readily reacts with water, it would do with sulfuric acid too.

19. "Samarium is one of the few lanthanides with a relatively accessible +2 oxidation state, alongside Eu and Yb."

This citation is factually correct but incorrectly sourced. The source is given as "Stephen T. Liddle; David P. Mills; Louise S. Natrajan, eds. (2022). The lanthanides and actinides: synthesis, reactivity, properties and applications. London. p. 213". The source is actually to a chapter in the book, namely "Organometallic Chemistry of Lanthanides" by Wenliang Huang and Paula L. Diaconescu, pp. 209 to 310.

Comments by Praseodymium-141[edit]

20-23

20. Source says:

The coordination chemistry in this oxidation state is essentially confined to the ions SmII, EuII and YbII. These are the only ones with an aqueous chemistry and their solutions may be prepared by ... These solutions are blood-red for SmII...

checkY Correct.

21. Source says:

At about 91 GPa samarium transforms to a body-centered tetragonal structure...

checkY Correct.

22. Don't have access to the source. From the abstract, it says "For Ln=La,Ce,Pr, Nd, Sm, a face-centered cubic compound is obtained from each reaction. The cell parameters are respectively 5.144, 5.089, 5.031, 4.994, and 4.943 ± 0.005A˚. The compounds appear golden yellow with a metallic luster."

checkY So, I think it should be.

23. Again I don't have access to the source. From the abstract, it says:

Structures and Raman spectra of lanthanide sesquioxide single crystals with A-type trigonal structure (La2O3, Pr2O3, Nd2O3, Sm2O3) and B-type monoclinic structure (Sm2O3, Eu2O3, Gd2O3) are compared. The B form (C32h or C2m, Z=6) derives from the A form (D33d or P3m1, Z=1) by a slight lattice deformation, implying a splitting of D3d and C3v atomic positions into less symmetrical C2h and Cs sites.

checkY So it should be.

24. Don't have access at all.

25. Don't have access. Here the abstract doesn't really tell much about it.

26. Don't have full access. Hexagonal does not be seem to be said in the source.

27. Don't have access at all. The title seems to be talking about its structure at least.

28

28. In abstract:

High pressure, high temperature techniques have been used to synthesize SmB2 and GdB12. The diboride has a hexagonal AlB2-type structure and the dodecaboride has a cubic UB12-type structure. Lattice parameters are a = 3.31 A, c = 4.019 A ...

checkY Seems to be enough already.

29. Don't have access. The abstract doesn't say much.

30. Don't have access. Might have structres on SmB4, SmB6 and SmB66 but I'm not sure.

31. Don't have access.

32. Don't have access. Definitely talks about SmC2, not so sure about Sm2C3.

33

33. checkY Definitely shows this.

34. Abstracts shows that it is about the right topic. Unable to verify, though.

35

35. checkY Shows.

36. Don't have access.

37. Don't have access.

38. Don't have access, probably shows though.

39. Don't have access.

40. Don't have access.

41. Don't have access.

42-43

42. checkY Definitely shows this.

43. checkY Shows.

44. Don't have access.

45. Not sure.

46

46. checkY Shows.

47. Don't have access (right now).

48-49

48. checkY Shows.

49. checkY Shows.

50. Don't have access.