aleksander bilewicz instytut chemii i techniki...
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Chemistry of superheavy elements
Aleksander Bilewicz
Instytut Chemii i Techniki Jądrowej
Konferencja Przyszłość fizyki jądrowej niskich energii w Polsce
a rozwój krajowej infrastruktury badawczej
Środowiskowe Laboratorium Ciężkich Jonów UW
14-15 stycznia 2019
Why we study super-heavy elements?
• How many elements can exist? chemical restrictions
• How relativistic effects can affect the chemical properties of elements
• Construction of the periodic table
2
2
00
me
4πr
=
0,4
0,5
0,6
0,7
0,8
0,9
1
0 10 20 30 40 50 60 70 80 90 100 110 120Z
c137,035
ZVr =
c137,035
ZVr =
<r1s>rel/<r1s>
2
0
c
v1
mm
−
=
orbital 1s
spin-orbital coupling
p
p1/2
p3/2
d5/2
d3/2
d
Relativistic effects in chemistry
• Noble gold [Xe]5d106s1
• Liquid mercury [Xe]5d106s2
• Yellow color of gold and cesium
• Anion Au-
• Low oxidation states
• Tl+ , [Xe]5d106s26p1/2
• Pb2+, [Xe]5d106s26p21/2
• Bi+, [Xe]5d106s26p21/26p3/2
• Po2+ [Xe]5d106s26p21/26p2
3/2
2018
Transaktynowce >103
Transfermowce > 100
Superciężkie > 103
6s orbital
J Autschbach,S Siekierski, J.Coput.Chem. 23 (2002) 808.
Cn - [Rn] 5f146d107s2
Fl - [Rn] 5f146d107s27p1/22
Rutherfordium 267Rf 2.5 hours
Dubnium 268Db 29 hours
Seaborgium 269Sg 14 minutes
Bohrium 270Bh 1 minute
Hassium 270Hs 10 seconds
Meitnerium 278Mt 7.6 seconds
Darmstadtium 281Ds 9.6 seconds
Roentgenium 282Rg 1.6 minutes
Copernicium 285Cn 29 seconds
Nihonium 286Nh 9.5 seconds
Flerovium 289Fl 1.9 seconds
Moscovium 290Mc 650 milliseconds
Livermorium 293Lv 57 milliseconds
Tennessine 294Ts 51 milliseconds
Oganesson 294Og0.69 milliseconds]
Criteria for chemical studies to
be carried out on a transactinide,
• at least four atoms must beproduced,
• the half-life of the isotope must be at least 1 second,
• rate of production must be at least one atom per week.
Faza 1 Faza 2
1
2
3
4
5
6
Faza 1 Faza 2
Classical system
One atom chemistry
= 5
=dK
=dK
=dK
=dK
=dK
0dK =
5dK =
Partition
technique
Solid state– gas
liquid – liquid
liquid – solid state
F2CF1C
dK =
Techniki badań
Termochromatography
A
R
C
A
A
I
D
A
Liquid chromatography
Window/Target (242,244Pu)
Beam (48Ca)
Beam stop
SiO2-FilterTa metal850°C
Quartz column
Cryo On-line Detector (4p COLD)
Carrier gas He/Ar (70/30)
Teflon capillary
(32 pairs PIN diodes, one side gold covered)
Hg Loop
Temperature gradient: 35°C to – 180 °C
T
l
Rn
The Cn and Fl experiments
112,114?
Recoil chamber
Quartz inlay
242Pu (48Ca,3n)287Fl - 3.5 pb
Adsorption of Cn on gold surface
Cn is similar to Hg but more volatile
-200
-150
-100
-50
0
50
-200
-150
-100
-50
0
50
-200
-150
-100
-50
0
502 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
0
10
20
30
40
50
icegold
219Rn
185Hg
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
0
10
20
30
40
50
283112
283112
ice
219Rn
185Hg
Re
l. y
ield
/ d
ete
cto
r, %
gold283
112
Te
mp
era
ture
, °C
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
0
10
20
30
40
50
Detector #
icegoldc)
b)
219Rn
185Hg
a)
R.Eichler et al. Nature 447 (2007) 72–75
-200-150-100-50050
-200-150-100-50050
-200-150-100-50050
0369
1215
(288
114)
288114
0369
1215
Re
l. y
ield
/ d
ete
cto
r, %
Te
mp
era
ture
, °C
287114
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
0369
1215
(289
114-->285
112)
Detector #
gold ice
-88°C
-90°C
-93°C
-4°C
Z=112
A. Yakushev et al. Inorg. Chem. 2014, 53, 1624−1629
Fl gas chemistry
A. Yakushev et al. Inorg. Chem. 2014, 53, 1624−1629
Hydrolysis in Group 4 Ti>Rf>Zr>Hf
OM+H
H
Ionic radius - rj
Rf4+ >Hf4+ > Zr4+ > Ti4+
kation ri (pm)
(CN=8)
pK1h
Ca2+ 112 13,22
Sr2+ 126 13,83
Ba2+ 142 14,07
Ra2+ 148 14,07
kation
ri,
pm
pK1h
kation
ri,
pm
pK1h
kation
ri,
pm
pK1h
Cu+
Ag+
Au+
77
115
137
-
12
3.8
Zn2+
Cd2+
Hg2+
74
95
102
8.96
10.08
3.40
Ga3+
In3+
Tl3+
62.0
80.0
88.5
3.6
4.0
0.6
Grupa 11 Grupa 12 Grupa 13
Grupa 2
Stałe hydrolizy
Perspectives of SHE research in Poland
1. Studies on Cn2+ hydrolysis
2. Termochromatography studies of chelates Rf, Db, Fl
3. Electrochemical studies of Cn and Fl