the chemistry of the transactinide elements
TRANSCRIPT
The Chemistry of the Transactinide Elements
Matthew MacLennanCHEM 540C
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Rf Db Sg Bh Hs Mt Ds Rg
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Nuclear Effects
• Protons, neutronsmagic numbers
• 2, 8, 20, 28, 50, 82• Island of stability • Magic numbers are
not permanent!• Spin-orbit coupling of
neutrons and protons
Warner, D. Nature 2004, 430, 517-519.Schiffer, J.P.; Freeman, S.J.; Caggiano, J.A.; Deibel, C.; Heinz, A.; Jiang, C.-L.; Lewis, R.; Parikh, A.; Parker, P.D.; Rehm, K.E.; Sinha, S.; Thomas, J.S. Phys. Rev. Lett. 2004, 92(16), 162501-1.
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Electronic Effects
• Relativistic effects –orbital contraction/expansion
• Spin-orbit coupling
Schädel, M. Angew. Chem. Int. Ed. 2006, 45, 368-401. 4
Architecture of Periodic Table
Ds Rg
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Preamble – “As Big as a Barn”
• Low production rates• Barn = 10-24 cm2; shed = 10-24 b
Schädel, M. J. Nucl. Radiochem. Sci. 2002, 3(1), 113-120. 6
Preamble Continued
• Need harsh conditions (acids)• Detectable decay (i.e. not SF); usually α
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Group 4
4
261Rf78 s
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Group 4
• MX4, MX62-, MX7
3-
• Liquid-phase experiments confirm
Haba, H. et al. J. Am. Chem. Soc. 2004, 126, 5219-5224. 9
Group 4• Test with pseudo-homologue Th, Pu• 8M HNO3
• Chloride complexation Rf>Zr>Hf
Haba, H. et al. J. Nucl. Radiochem. Sci. 2002, 3(1), 143-146. 10
Group 5
5?
262Db34 s
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Group 5
• Adsorption onto glass surfaces (KCl, HNO3) (Group 4 = no sorption)
Hoffman, D.C.; Lee, D.M. J. Chem. Educ. 1999, 76(3), 331-347. 12
Group 5
• Liquid-liquid extractions of Db, Ta, Nb, Pa in TiOA, HCl/0.03 M HF
• Ta in organic phase• Db eluting
between Nb, Pa
Schädel, M.; Angew. Chem. Intl. Ed. 2006, 45, 368-401. 13
Group 6
VI? ?
X255,256Sg7-20 s
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Group 6
• Group 6 forms neutral or anionic oxides, oxyhalides
• HNO3/HF[MO3F]-, [MO2F3]-, MO2F2
• Pseudo-homologue U UO22+
Schädel, M.; J. Alloys Compd. 1998, 271-273, 312-315. 15
Group 6
• Volatility MoO2Cl2>WO2Cl2≈SgO2Cl2• Sg may be least volatile element yet
Türler, A. et al. Angew. Chem. Int. Ed. 1999, 38, 2212-2213. 16
Group 7
VII? ?
X
X
267Bh17 s
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Group 7
• DFT calculationsMO3Cl most stable
• Volatility: TcO3Cl>ReO3Cl>BhO3Cl
Eichler, R. et al. Nature, 2000, 407, 63-65. 18
Group 8
VIII? ?
X
X
269Hs10 s
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Group 8
Düllmann, Ch.E. et al. Czech. J. Phys., 2003, 53, A291-A298.
• Volatile tetroxides• 2NaOH+HsO4Na2[HsO4(OH)2]
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Group 9, 10, 11
IX X XI? ?
X
XHalf-lives0.1 s
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Group 12
XII? ?
X
X
? ? ?
2831123.8 s
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Group 12
Eichler, R. et al. Nature, 2007, 447, 72-75.
• Covalent bond with Au• Relativistic effects?
Eichler, R. et al. Angew. Chem. Int. Ed. 2008, 47, 3262-3266. 23
“It’s Just a Phase You’re Going Through…”
• 112 is more volatile than Hg!• Gaseous metal?
Eichler, R. et al. Angew. Chem. Int. Ed. 2008, 47, 3262-3266. 24
MX4 MO2X2
MOX4
MO3X MO4MX5
Some More Trends
? ?
X
X
? ? ? ?
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Concluding Remarks
• Periodic table generally good tool• Lacking for subtle properties• Innovative experimental set-ups• Qualitativemore experiments to perform• 109-114
Nuclear Chemist when askedto provide a straight answer…
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Thank you so much!
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