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  • Astatine partitioning between nitric acid and conventional solvents: indication of covalency in ketone complexation of AtO +
Title: Astatine partitioning between nitric acid and conventional solvents: indication of covalency in ketone complexation of AtO +
Astatine-211 has been produced at Texas A&M University on the K150 cyclotron, with a yield of 890 ± 80 MBq through the 209 Bi(α,2n) 211 At reaction via an 8 h bombardment with a beam current of 4–8 μA and an α-particle beam energy of 28.8 MeV. The target was then dissolved in HNO 3 and the extraction of 211 At was investigated into a variety of organic solvents in 1–3 M HNO 3 . Extraction of 211 At with distribution ratios as high as 11.3 ± 0.6, 12.3 ± 0.8, 42.2 ± 2.2, 69 ± 4, and 95 ± 6 were observed for diisopropyl ether, 1-decanol, 1-octanol, 3-octanone, and methyl isobutyl ketone, respectively, while the distribution ratios for 207 Bi were ≤0.05 in all cases. The extraction of 211 At into both methyl isobutyl ketone and 3-octanone showed a strong, linear dependence on the HNO 3 initial aqueous concentration and better extraction than other solvents. DFT calculations show stronger binding between the carbonyl oxygen of the ketone and the At metal center.  more » « less
Award ID(s):
1664866
NSF-PAR ID:
10252431
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Chemical Communications
Volume:
56
Issue:
63
ISSN:
1359-7345
Page Range / eLocation ID:
9004 to 9007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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