Alchemy in the
1
1
H
3
Li
11
Na
19
K
37
Rb
55
Cs
87
Fr
2
4
Be
12
Mg
20
Ca
38
Sr
56
Ba
88
Ra
3
21
Sc
39
Y
st
21
4
22
Ti
40
Zr
72
Hf
104
Rf
5
23
V
41
Nb
73
Ta
105
Db
6
24
Cr
42
Mo
74
W
106
Sg
7
25
Mn
43
Tc
75
Re
107
Bh
8
26
Fe
44
Ru
76
Os
108
Hs
9
27
Co
45
Rh
77
Ir
109
Mt
10
28
Ni
46
Pd
78
Pt
110
Ds
11
29
Cu
47
Ag
79
Au
111
Uuu
12
30
Zn
48
Cd
80
Hg
112
Uub
13
5
B
13
Al
31
Ga
49
In
81
Tl
113
Uut
58
Ce
90
Th
59
Pr
91
Pa
60
Nd
92
U
61
Pm
93
Np
62
Sm
94
Pu
63
Eu
95
Am
64
Gd
96
Cm
65
Tb
97
Bk
66
Dy
98
Cf
67
Ho
99
Es
century
14
6
C
14
Si
32
Ge
50
Sn
82
Pb
114
Uuq
15
7
N
15
P
33
As
51
Sb
83
Bi
115
Uup
16
8
O
16
S
34
Se
52
Te
84
Po
116
Uuh
17
9
F
17
Cl
35
Br
53
I
85
At
68
Er
100
Fm
69
Tm
101
Md
70
Yb
102
No
71
Lu
103
Lr
18
2
He
10
Ne
18
Ar
36
Kr
54
Xe
86
Rn
????
The quest for superheavy elements
57
La
89
Ac
Alchemy in the 21st century R-D Herzberg
Elementary, my dear Watson?
History
What is an element?
Nuclear Physics for pedestrians
Chemistry on single atoms
Outlook
Alchemy in the 21st century R-D Herzberg
A brief history
Aristoteles
384-322 BC
Alchemy in the 21st century R-D Herzberg
The first Periodic table
Dimitri Mendeleev, published in 1869.
67 elements were known at that time
Alchemy in the 21st century R-D Herzberg
Modern History
Alchemy in the 21st century R-D Herzberg
Sir, Finding new Elements, Sir!
Alchemy in the 21st century R-D Herzberg
The role of the nucleus
The element is determined by the
Number of protons (Z)
Ernest Rutherford, 1909
Alchemy in the 21st century R-D Herzberg
The Segre chart
Alchemy in the 21st century R-D Herzberg
Sic transit gloria mundi
• Nuclei decay via 4 basic
modes:
– Alpha decay (Z-2, N-2)
– Beta(-) decay (Z+1, N-1)
– Beta(+) decay (Z-1, N+1)
– Fission into two large
fragments and a few
neutrons
Alchemy in the 21st century R-D Herzberg
What determines stability?
Number of protons
114
peak of Th,U
peak of Pb
82
strait of
radioactivity
sea of instability
50
island of
spherical
SHE
peak of Sn
Magic Numbers
20
peak of Ca
20
82
Neutrons
Protons
20, 50,
20, 50
82, 126
82,
126
Number of neutrons
Alchemy in the 21st century R-D Herzberg
???
184
Magic Shells
M Bender et al, Physics Letters B 515 (2001) p 42
Alchemy in the 21st century R-D Herzberg
What do the theorists say?
• Predictions vary
wildly.
• Z = 124 ?
• Z = 126 ?
• Z = 114 ?
• A whole region?
S. Cwiok et al, Nuclear Physics A 611 (1996) p 211
Alchemy in the 21st century R-D Herzberg
Z = 124
Z = 126
Z = 114
Shell Positions for
From M. Bender et al., PRC 60 (1999) 034304
R-D Herzberg
298114
Different Skyrme Forces
Nuclear EOS from
18 different Skyrme
parametrisations
S. Typel, B.A. Brown,
PRC 64 027302.
ρ0 = 0.16 fm-3
All agree around
nuclear density
Neutron density
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Creation of new elements
• Neutron capture (up to Z=100)
– in reactors
– in bombs
– in stars?
240Pu + n
241Pu
239Np + n 240Np + n 241Np
236U
238U + n 239U
Alchemy in the 21st century R-D Herzberg
Modern methods
Alchemy in the 21st century R-D Herzberg
Accelerator based methods
• “Hot” fusion
– Light projectile on radioactive target
U+Mg->Rf
Cf+Ca->118
• “Cold” fusion (Up to Z=112)
– Heavy projectile on Pb/Bi targets
Pb+Cr -> Sg Pb+Fe -> Hs Pb+Zn -> 112
Alchemy in the 21st century R-D Herzberg
Challenges
Reaction probabilities get small:
Measured in “barn”
If 1 b is taken as 1m x 1m on a dartboard
1 pb is only 1µm x 1 µm
Hit that!
Alchemy in the 21st century R-D Herzberg
Like charges repel 
Energy ->
+
Costs
Energy!
0
++
+
Gain Energy!
Alchemy in the 21st century R-D Herzberg
Z=116
116
GSI colloquium 17 Feb. 2004
Alchemy in the 21st century R-D Herzberg
Identification via alpha chains
208Pb
+
64Ni
→
271Ds
271110 272110
+n
α1
τ=2.9ms τ=120ms
5
α1
α1
267Hs
0
1ms
0.1s
10s
τ=77ms
0
5
1ms
α2
0.1s
10s
τ=1.0s
0
5
1ms
α4
0
5
1ms
α5
0
10µs
α5
1ms
1000s
0.1s
τ=3.7s
0.1s
10s
α4
10s
1000s
259Rf
α2
5
0
263
1000s
α3
Counts/100keV
Counts/bin
0
5
5
α3
Sg
8
267Hs
α2
8
10s
Tdecay
263Sg
10
9
5
11
α3
0
8
25910
Rf
9
5
11
α4
1000s
8
5
9
255No
0
255Md
11
9
0
τ=220s
255No
0.1s
271110272110
1000s
7
8
251Fm
9
Alchemy in the 21st century R-D Herzberg
α5
255Md
10
Eα (MeV)
251Fm K. Morita et al, Workshop on SHE, GSI, Feb 2004
11
10
11
SHIP at GSI
Suppression of beam by
1:1012
Alchemy in the 21st century R-D Herzberg
Detector Systems
• Position sensitive
• All alpha decays
happen at the same
place!
• Identify elements
via genetic
relationships
Alchemy in the 21st century R-D Herzberg
The whole process summarised
n
n
288
115
Spherical shells
Z=114 N=184
neutrons
and γ−rays
n
α-decays
and γ−rays
2 x 134 Te
Spherical shells
Z=50 N=82
Fusion
268
104 Spontaneous fission
243Am-target
48Ca-projectile
268
105
Deformed shells
Z=108 N=162
EC
and X−rays
Alchemy in the 21st century R-D Herzberg
Are we there yet?
We are up to Z = 118 now.
Z = 114
N = 184
Alchemy in the 21st century R-D Herzberg
Element 115
GENERAL PROPERTIES
Name:
Ununpentium
Symbol:
Uup
Atomic Number:
115
Atomic Weight:
UNKNOWN
Density @ 293K:
31.5g/cm³
Atomic Volume:
13.45cm³/mol
Group:
Superheavy Elements
Discovered:
1989
STATES
State:
Solid
Boiling Point:
3530°C
Melting Point:
1740°C
Heat of Vaporisation:
UNKNOWN kJ/mol
APPEARANCE AND CHARACTERISTICS
Structure:
FCC Face-centered
cubic
Color:
Reddish-orange
Uses:
Reactor Fuel
Toxicity:
UNKNOWN
Hardness:
UNKNOWN mohs
Characteristics:
Stable
www.abovetopsecret.org - deny ignorance
• Useful in Antigravity devices
• Generally found in Area 51
Alchemy in the 21st century R-D Herzberg
What do I do?
252,254No
250Fm
Alchemy in the 21st century R-D Herzberg
Single Particle Orbitals
protons
neutrons
R. Chasman et al., Rev. Mod. Phys. 49, 833 (1977)
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Today
PPNP61 (08) 674
R-D Herzberg
Recognised effort:
IOP Nuclear and Particle Physics
Division Prize 2008
“We are very pleased to
announce that Rodi Herzberg
from the University of Liverpool
has been awarded the IOP
Nuclear and Particle Physics
Division Prize for 2008. Rodi
was nominated by the Nuclear
Physics Group in recognition of
his important work on
superheavy nuclei. “
Alchemy in the 21st century R-D Herzberg
Copper, Silver, Gold, ???
111
Ag
?
Au
Cu
111
?
Alchemy in the 21st century R-D Herzberg
10
28
Ni
46
Pd
78
Pt
110
Ds
11
29
Cu
47
Ag
79
Au
111
Uuu
12
30
Zn
48
Cd
80
Hg
112
Uub
Electron Configurations
Alchemy in the 21st century R-D Herzberg
Take a pinch of this and mix it…
The Art of Chemistry on Single Atoms
Standard adsorption enthalpy:
-∆HadsAu [kJ/mol]
250
Pb
R. Eichler et al.
• Gas Phase Chemistry
200
Bi
Po
150
Hg
• Use decay position toAt measure a
physical property
50
100
0
0
Rn
Xe
Kr
-∆Hads(Au) = (1.1±0.1)*∆Hsubl+(8.4±5.4) [kJ/mol]
R2 = 0.991
50
100
150
200
Standard sublimation enthalpy:
∆Hsubl [kJ/mol]
Alchemy in the 21st century R-D Herzberg
25
Predictions for Element 112
Extrapolations
Relativistic
K.S. Pitzer,
J. Chem.
Phys. 63,
V. Pershina et al.,
1032 (1975)
Noble gas like
Chem. Phys.
Lett., 365, 176
(2002)
B. Eichler,
Kernenergie 10, 307 (1976 )
B. Eichler,
PSI Report 03-01, Villigen
(2000)
Volatile metal
Alchemy in the 21st century R-D Herzberg
Thermochromatography
S. Soverna
January 2004
48Ca-
Beam
rotating
238U-target
(1.6 mg cm2)
oven
(850 °C)
~10 m
PFA-capillary
quartz
recoil
chamber wool filter
Oven
(1000 °C)
H. Gaeggeler, priv comm
.
thermostat
(+35 °C)
Ta-/Ti-getter
PIN-diodes opposite
surface
a
Alchemy in the 21st century R-D Herzberg
N2 (liq.)
(-196 °C)
Experimental Data
Compare Hs and Os
248Cm(26Mg,
HsO4
5,4n)269,270Hs
OsO4
Duellmann et al, Nature 418 (2002), p 859
Alchemy in the 21st century R-D Herzberg
Element 112 Chemistry
R. Eichler et al., Nature 447, 72-75(3 May 2007)
Alchemy in the 21st century R-D Herzberg
Quo vamus?
• The effort to reach even heavier elements
is well under way and a major goal in
modern nuclear physics
• Dedicated facilities are needed to provide
the necessary beams over a long period
(months!)
Alchemy in the 21st century R-D Herzberg
Further information
• On Beyond Uranium: Journey to the
End of the Periodic Table
S. Hofmann, Taylor & Francis, 2003
• The Transuranium People
D. C. Hoffman, A. Ghiorso, G.T. Seaborg
ICP 2000
Alchemy in the 21st century R-D Herzberg
And finally:
“Whatever the expense of improving
education, it is an investment in the
future we must make. Excellence
Costs. But in the long run mediocrity
costs much more.”
Glenn T Seaborg
Nobelprize 1951
Alchemy in the 21st century R-D Herzberg
Our Young Scientist Program in
action:
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