Isotopes of ununoctium
Ununoctium (Uuo) is an artificial element created in particle colliders, and thus a standard atomic mass cannot be given. Like all artificial elements, it has no stable isotopes. The first (and so far only) isotope to be synthesized was 294Uuo in 2006; it has a half-life of 890 microseconds.
Contents |
Table [edit]
| nuclide symbol |
Z(p) | N(n) | isotopic mass (u) |
half-life | decay mode(s) | daughter isotope(s) |
nuclear spin |
|---|---|---|---|---|---|---|---|
| 294Uuo | 118 | 176 | 294.21392(71)# | 890 µs | α | 290Lv |
Notes [edit]
- Values marked # are not purely derived from experimental data, but at least partly from systematic trends.
- Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values from Ame2003 denote one standard deviation. Values from IUPAC are expanded uncertainties.
Theoretical [edit]
Theoretical calculations done on the synthetic pathways for, and the half-life of, other isotopes have shown that some could be slightly more stable than the synthesized isotope 294Uuo, most likely 293Uuo, 295Uuo, 296Uuo, 297Uuo, 298Uuo, 300Uuo and 302Uuo.[1][2][2] Of these, 297Uuo, might provide the best chances for obtaining longer-lived nuclei,[1][2] and thus might become the focus of future work with this element. Some isotopes with many more neutrons, such as some located around 313Uuo, could also provide longer-lived nuclei.[3]
Target-projectile combinations leading to Z=118 compound nuclei [edit]
The below table contains various combinations of targets and projectiles which could be used to form compound nuclei with Z=118.
| Target | Projectile | CN | Attempt result |
|---|---|---|---|
| 160Gd | 136Xe | 296Uuo | Reaction yet to be attempted |
| 208Pb | 86Kr | 294Uuo | Failure to date |
| 232Th | 64Ni | 296Uuo | Reaction yet to be attempted |
| 238U | 58Fe | 296Uuo | Reaction yet to be attempted |
| 244Pu | 54Cr | 298Uuo | Reaction yet to be attempted |
| 248Cm | 50Ti | 298Uuo | Reaction yet to be attempted |
| 250Cm | 50Ti | 300Uuo | Reaction yet to be attempted |
| 249Cf | 48Ca | 297Uuo | Successful reaction |
| 252Cf | 48Ca | 300Uuo | Reaction yet to be attempted |
| 257Fm | 40Ar | 297Uuo | Reaction yet to be attempted |
Theoretical calculations on evaporation cross sections [edit]
The below table contains various targets-projectile combinations for which calculations have provided estimates for cross section yields from various neutron evaporation channels. The channel with the highest expected yield is given.
DNS = Di-nuclear system ; σ = cross section
| Target | Projectile | CN | Channel (product) | σ max | Model | Ref |
|---|---|---|---|---|---|---|
| 208Pb | 86Kr | 294Uuo | 1n (293Uuo) | 0.1 pb | DNS | [4] |
| 208Pb | 85Kr | 293Uuo | 1n (292Uuo) | 0.18 pb | DNS | [4] |
| 252Cf | 48Ca | 300Uuo | 3n (297Uuo) | 1.2 pb | DNS | [5] |
| 251Cf | 48Ca | 299Uuo | 3n (296Uuo) | 1.2 pb | DNS | [5] |
| 249Cf | 48Ca | 297Uuo | 3n (294Uuo) | 0.3 pb | DNS | [5] |
References [edit]
- Isotope masses from:
- M. Wang, G. Audi, A.H. Wapstra, F.G. Kondev, M. MacCormick, X. Xu, et al. (2012). "The AME2012 atomic mass evaluation (II). Tables, graphs and references.". Chinese Physics C, 36 (12): 1603–2014. doi:10.1088/1674-1137/36/12/003.
- G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties". Nuclear Physics A 729 (1): 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
- ^ a b P. Roy Chowdhury, C. Samanta, and D. N. Basu (January 26, 2006). "α decay half-lives of new superheavy elements". Phys. Rev. C 73: 014612. arXiv:nucl-th/0507054. Bibcode:2006PhRvC..73a4612C. doi:10.1103/PhysRevC.73.014612. Retrieved 2008-01-18.
- ^ a b c C. Samanta, P. Roy Chowdhury and D. N. Basu (April 6, 2007). "Predictions of alpha decay half lives of heavy and superheavy elements". Nuclear Physics A 789 (1-4): 142–154. arXiv:nucl-th/0703086. Bibcode:2007NuPhA.789..142S. doi:10.1016/j.nuclphysa.2007.04.001. Retrieved 2008-01-18.
- ^ S B Duarte, O A P Tavares, M Gonçalves, O Rodríguez, F Guzmán, T N Barbosa, F García and A Dimarco (2004). "Half-life predictions for decay modes of superheavy nuclei". J. Phys. G: Nucl. Part. Phys. 30 (10): 1487–1494. Bibcode:2004JPhG...30.1487D. doi:10.1088/0954-3899/30/10/014. Retrieved 2008-01-18.
- ^ a b Feng, Zhao-Qing; Jin, Gen-Ming; Li, Jun-Qing; Scheid, Werner (2007). "Formation of superheavy nuclei in cold fusion reactions". Physical Review C 76 (4): 044606. arXiv:0707.2588. Bibcode:2007PhRvC..76d4606F. doi:10.1103/PhysRevC.76.044606.
- ^ a b c Feng, Z; Jin, G; Li, J; Scheid, W (2009). "Production of heavy and superheavy nuclei in massive fusion reactions". Nuclear Physics A 816 (1-4): 33. arXiv:0803.1117. Bibcode:2009NuPhA.816...33F. doi:10.1016/j.nuclphysa.2008.11.003.
| Isotopes of ununseptium | Isotopes of ununoctium | Isotopes of ununennium |
| Table of nuclides | ||
| Isotopes of the chemical elements | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 H |
2 He |
||||||||||||||||
| 3 Li |
4 Be |
5 B |
6 C |
7 N |
8 O |
9 F |
10 Ne |
||||||||||
| 11 Na |
12 Mg |
13 Al |
14 Si |
15 P |
16 S |
17 Cl |
18 Ar |
||||||||||
| 19 K |
20 Ca |
21 Sc |
22 Ti |
23 V |
24 Cr |
25 Mn |
26 Fe |
27 Co |
28 Ni |
29 Cu |
30 Zn |
31 Ga |
32 Ge |
33 As |
34 Se |
35 Br |
36 Kr |
| 37 Rb |
38 Sr |
39 Y |
40 Zr |
41 Nb |
42 Mo |
43 Tc |
44 Ru |
45 Rh |
46 Pd |
47 Ag |
48 Cd |
49 In |
50 Sn |
51 Sb |
52 Te |
53 I |
54 Xe |
| 55 Cs |
56 Ba |
* | 72 Hf |
73 Ta |
74 W |
75 Re |
76 Os |
77 Ir |
78 Pt |
79 Au |
80 Hg |
81 Tl |
82 Pb |
83 Bi |
84 Po |
85 At |
86 Rn |
| 87 Fr |
88 Ra |
** | 104 Rf |
105 Db |
106 Sg |
107 Bh |
108 Hs |
109 Mt |
110 Ds |
111 Rg |
112 Cn |
113 Uut |
114 Fl |
115 Uup |
116 Lv |
117 Uus |
118 Uuo |
| * | 57 La |
58 Ce |
59 Pr |
60 Nd |
61 Pm |
62 Sm |
63 Eu |
64 Gd |
65 Tb |
66 Dy |
67 Ho |
68 Er |
69 Tm |
70 Yb |
71 Lu |
||
| ** | 89 Ac |
90 Th |
91 Pa |
92 U |
93 Np |
94 Pu |
95 Am |
96 Cm |
97 Bk |
98 Cf |
99 Es |
100 Fm |
101 Md |
102 No |
103 Lr |
||
