Superheavy Element Research Superheavy Element Research

www.superheavies.de

c.e.duellmann@gsi.de

Superheavy Element Research

News from GSI and Mainz

Christoph E. Düllmann

Johannes Gutenberg University Mainz

GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt

Helmholtz Institute Mainz

FIAS Colloquium

Frankfurt Institute of Advanced Studies, Frankfurt, Germany, October 20, 2011

The next 60 minutes:

• Superheavy elements – Brief introduction, introduction status of

the field

• Facilities + program at GSI, U. Mainz, HIM

• Research at the TASCA gas-filled recoil separator

– Physics Example

Search for Element 120

– Chemistry Example

Element 114: noble metal or noble gas?

• Bi Brief fwrap-up

Ch.E. Düllmann – Superheavy element research – FIAS Colloquium – Frankfurt Institute for Advanced Studies, Frankfurt – October 20, 2011

82

50

Peak of

Calcium

20

Map of the Nuclear Landscape

Peak of Tin

Uranium Summit

Peak of Lead

20 82 126

Flerov & Ilyinov (1986)


Potential

ene ergy / MMeV

Influence of shell effects on fission barrier

2.5 MeV

~0.5 MeV LD + shell

no barrier!

Cf

250 50

98 152

LD 250 25098 98152

SSg

268 268106162 106 162

298 114184

298

114 114184

macroscopic barrier:

Disappears at Z ~ 104!

Deformation β2 after A. Sobiczewski / S. Hofmann


Potential

ene ergy / MMeV

Influence of shell effects on fission barrier

LD + shell

no barrier!

Cf

250 50

98 152

LD 250 25098 98152

SSg

268 268106162 106 162

298 114184

298

114 114184

macroscopic barrier:

Disappears at Z ~ 104!

with shell structure:

spherical � deformed ground state

fi fission i bbarrier i iis also l > 0 ffor

elements with Z �104.

some fission barriers have

complicated shapes, multiplyhumped

elements that exist only thanks

to shell effects:

superheavy elements

Deformation β2 after A. Sobiczewski / S. Hofmann


~114 –

126 (?)

82

50

20

Map of the Nuclear Landscape

Island of Stability

20 82 126

184


Cross Sections in Hot / Cold / 48 Ca Induced Fusion Reactions

1 pb: ~1-2 Events per Week

Compilation: A. Yakushev, Habilitation thesis, TU Munich, 2009


Cross Sections in Hot / Cold / 48 Ca Induced Fusion Reactions

Compilation: A. Yakushev, Habilitation thesis, TU Munich, 2009


Unique Combination for SHE Studies

ECR +

Stable

UNILAC targets

Beam

TRIGA-

Actinide

targets g

-LASER LASER

Radiochem.

-TRAP labs

SHIP

TASCA

Chemistry

SHIPTRAP

TASISpec

Chemical

theory


HIM – The New Helmholtz Institute Mainz

HIM Director: Frank Maas

-

-J. Dvorak (IRiS)

(currently on leave of absence)

-

Chemistry Physics

CED N.N.

Toward a dedicated cw LINAC for SHE; ...


Toward A New Accelerator for SHE Research

ps

sity / pp

m Intens

Beam

Pulsed

0 10 20 30 40

Time / ms



ps

sity / pp

m Intens

Beam

Pulsed �� cw Beams

0 10 20 30 40

Time / ms



ps

sity / pp

m Intens

Beam


0 10 20 30 40

Time / ms



Beamm

Intenssity

/ ppps

Perspectives:


New dedicated SHE cw cw-LINAC LINAC

In combination with new 28 GHz ECR ion source:

10x higher beam intensity

0 10 20 30 40

Time / ms


Toward a Dedicated SHE LINAC

UNILAC not suited for simultaneous

FAIR (A>180 (A>180, �3 �3 Hz Hz, 100 �s �s pulses)

SHE operation (A

Toward a Dedicated SHE LINAC

UNILAC not suited for simultaneous

WW. Barth

S. Mickat

U. Ratzinger

FAIR (A>180 (A>180, �3 �3 Hz Hz, 100 �s �s pulses)

SHE operation (A

The Darmstadt/Mainz SHE Community

GSI Helmholtz Center for Heavy ion Research, Darmstadt:

SHE Chemistry (TASCA / X1) Department:

Scientific staff

Technical staff

Diploma / PhD students

Ch.E. Düllmann, A. Yakushev, V. Pershina (Theory) [3]

E. Jäger, J. Krier, J. Runke (@ JG Univ. Mainz), B. Schausten, M. Grimm [5]

SHE Physics y (SHIP/SHIPTRAP) ( ) Department: p

F.P. Hessberger, N.N. (NF Rudolph), D. Ackermann, M. Block, S. Heinz, S. Hofmann [5]

H.-G. Burkhard [1]

Target Laboratory Laboratory, Detector Laboratory Laboratory, Experimental Electronics Electronics....

Johannes Gutenberg-University Mainz (Institute for Nuclear Chemistry):

Ch.E. Düllmann (SHE Chemistry), N.N. (NF Rudolph, SHE Physics); J.V. Kratz,

NN. TTrautmann, t N. N Wi Wiehl hl [3]

J. Even, D. Hild, S. Klein, D. Renisch, A. Vascon [5]

Ch. Mokry, P. Thörle-Pospiech

TTransuranium i TTarget t Lab: L b K. Eberhardt et al.

[2]

Helmholtz Institute Mainz:

Ch.E. Düllmann (SHE ( Chem.), ), F.P. Hessberger g ( (SHE Physics, y , interim), ), N.N. (NF ( Rudolph) p )

J. Dvorak (on leave), J. Khuyagbaatar, L.-L. Andersson, E. Rodriguez Minaya

J. Maurer, V. Yakusheva [6]


Current International Collaboration Partners

(SHE Chemistry / TASCA)

LBNL/UCB Berkeley (USA) U Lund (Sweden)

LLNL Livermore (USA) U Jyväskylä (Finland)

Vanderbilt U (USA) UOslo(Norway)

U Oslo (Norway)

ORNL Oak Ridge (USA) Chalmers U Gothenburg (Sweden)

UNAL Bogota (Columbia) PSI Villigen (Switzerland)

U Liverpool (UK) ITE Warschau (Poland)

U Surrey (UK) SINP Kolkata (India)

IMP Lanzhou (China)

JAEA Tokai (Japan)


TransActinide Separator and Chemistry Apparatus

A Separator for Actinide Based Reactions

www.gsi.de/tasca

M. Schädel, Eur. Phys. J. D 45 (2007) 67

A. Semchenkov et al., NIMB 266 (2008) 4153

Timeline

2002 goals defined

2003 community formed

2004 decision: gas-filled sep sep.

2005 start building TASCA

define commissioning prog.

2006 first beam in cave (Jan.)

first EVR in focal plane det.(Apr.)

2006-2008

TASCA commissioning

2008 commissioning completed:

Transactinides reached! Z=104

2009 Heaviest Element at GSI: Z=114

2011 Hunting element 120



A Separator for Actinide Based Reactions

www.gsi.de/tasca

M. Schädel, Eur. Phys. J. D 45 (2007) 67

A. Semchenkov et al., NIMB 266 (2008) 4153

Timeline

2002 goals defined

2003 community formed

2004 decision: gas-filled sep sep.

2005 start building TASCA

define commissioning prog.

2006 first beam in cave (Jan.)

first EVR in focal plane det.(Apr.)

2006-2008

TASCA commissioning

2008 commissioning completed:

Transactinides reached! Z=104

2009 Heaviest Element at GSI: Z=114

2011 Hunting element 120


Recoil Separators for SHE studies

Beam

Target

1) Synthesis of SHE; Decay studies

in Focal Plane Detectors

TASCA

TransActinide Separator

and Chemistry Apparatus

Particle Detector (�; e - ; SF)

Photon Detector (�; X)


Recoil Separators for SHE studies

Beam

Target

1) Synthesis of SHE; Decay studies

in Focal Plane Detectors

TASCA

Inert gas TransActinide Separator

(He, ( , Ar,...) , ) and Chemistry Apparatus

2) Preseparated SHE for chemical studies under low-background

conditions (Important for volatile p-Elements Z=112, 114, ...)

To chemistry y setup p

(e.g., gas phase

chromatography in

COMPACT)


SHE physics

at TASCA

Briefly looking back: element 114 in 2009

Hot topic 2011: search for new element 120


2009: The Element 114 TASCA Experiment

13 Decay Chains in 22 Days � Highest SHE Detection Rate

48Ca+ 244Pu � 292114* � 288114+4n / 289114+3n 4n Evaporation Channel:

284 284CCn +31

97 ms

-19

SF

SF

�

288 114

DGFRS

288 114

+0.27

0.80 -0.16s

� 9.94�0.06

�

TASCA

288 114

+0.24

0.47 -0.12 s

� 9.95�0.03

3n Evaporation Channel:

DGFRS

289 114

+1.2

2.6 -0.7 s

� 9.82�0.05

284 284CCn 285 285CCn +50

101 -25

ms

SF �

+13

29 -7 s

� 9.15�0.05 �

SF

281Ds +5.0

11.1 -2.7 s

281Ds +20

20 -7 s

SF

SF (�)

SF 277Hs +15

3 -1 ms

SF

SF

�

�

SF

289 289114 114

285 285CCn +30

30 -10 s

� 9.21�0.03

�

TASCA

289 114

+0.97

0.97 s -0.32

� 9.87�0.03

TASCA data:

Ch.E.Düllmann et al.,

PRL 104 (2010) 252701

J.M. Gates et al.

PRC 83 (2011) 054618

DGFRS Data

YYu.Ts. T Oganessian O i et t al., l

JPG 34 (2007) R165

PRC 69 (2004) 054607


244 Pu+ 48 Ca: High cross sections for element 114 confirmed

RRun 1 RRun 2

4n

Energies g studied at

TASCA

DGFRS Data

Oganessian et al.,

J. Phys. G, 2008

3n TASCA Data


PRL 104 (2010) 252701

JM J.M. GGates t et t al. l

PRC 83 (2011) 054618

Error bars include statistical errors.

TASCA systematic error is estimated to 14%.

Theory

V. Zagrebaev,

NPA 734 (2004) 164

10 pb! Largest

�� for predicted

spherical SHE


244 Pu+ 48 Ca: High cross sections for element 114 confirmed

RRun 1 RRun 2

4n

Energies g studied at

TASCA

DGFRS Data

Oganessian et al.,

J. Phys. G, 2008

3n TASCA Data


PRL 104 (2010) 252701

JM J.M. GGates t et t al. l

PRC 83 (2011) 054618

Error bars include statistical errors.

TASCA systematic error is estimated to 14%.

Theory

V. Zagrebaev,

NPA 734 (2004) 164

10 pb! Largest

�� for predicted

spherical SHE


Making Making new new elements

elements

E120 Z 0

Beam

22

Beam

50 Ti

Target

249 Cf

Asymmetry E*@BBass 31.7 31.7

23 51V 249Bk 35.9

24 54Cr 248Cm 33.0

25 55Mn 243Am 34.5

26 58Fe 244Pu 33.9

27 59 Co 237 Np 32 32.9 9

28 64Ni 238U 27.3

Similar arguments for E119 hint at

Ti+ 249 Bk as the preferred reaction

50 Ti+


crrosss

secctionn

/ fb

Choice of the optimum reaction: example E120

10 4

10 3

10 2

10

10 1

10 0

10 -1

10

10 -2

10 -3

Fe+Pu Zagrebaev Zagrebaev + et Greiner al. al

Ti+Cf Ti Cf Zagrebaev + Greiner

Cr+Cm Ni+U

Asymmetric

DGFRS

SHIP

Asymmetry

(More) symmetric

Adamian et al.

Liu et al.

Nasirov et al.

Siwek-Wilczynska et al.


crrosss

secctionn

/ fb


10 4

10 3

10 2

10

10 1

10 0

10 -1

10

10 -2

10 -3



Cr+Cm Ni+U

Asymmetric

DGFRS

SHIP

Asymmetry

(More) symmetric

Adamian et al.

Liu et al.

Nasirov et al.



crrosss

secctionn

/ fb


10 4

10 3

10 2

10

10 1

10 0

10 -1

10

10 -2

10 -3



Cr+Cm Ni+U

TASCA

Asymmetric

DGFRS

SHIP

Asymmetry

(More) symmetric

Adamian et al.

Liu et al.

Nasirov et al.


Conclusion:

� scales w/ asymmetry

Best reaction: 50 Ti+ 249 Cf

� predicted: 50 fb – 1 pb


50 Ti+ 249 Cf Excitation Function

05 0.5 mg/cm / 2 T t

2 Target

~ 4 MeV (lab)

V. Zagrebaev + W. Greiner, Phys. Rev. C 78 (2008) 034610

Maximum:

40 fb!


A new high-intensity transuranium target wheel for TASCA

Radiochemical labs at Mainz


A new high-intensity transuranium target wheel for TASCA

Radiochemical labs at Mainz

Making actinide targets

K. Eberhardt et al.

Used for E120 at

Ø Target g Wheel: 100 mm

Ø Beam Spot: 8 mm

Target g wheel tested up p to

2500 particle·nA

E. Jäger, T. Torres, J. Krier


Z

50 Ti+ 249 Cf Very short-lived!

Mt

Hs

Bh

Sg

Db

Rf

266Mt

1.7ms

265Hs

Ds

266Hs

111

269Ds

Rg

270Ds

272Rg

1.6ms

271Ds

02ms 0.2ms 01ms 0.1ms 56 ms

268Mt

42 ms

267Hs

2 ms 2.3ms 49 ms

264Bh

0.97 s 0.94 s

263Sg

0.9 m

265Bh

264Sg

37 ms

262Db 263Db

34 s

261Rf

68 s

27 s

262Rf

2 s?

266Bh

1.1 s

265Sg

16 s

267Bh

17 s

266Sg

0.36 s

263Rf

8 s? 160 160

270Mt

0.57 s

269Hs

14 s

270Hs

~23 s

113

112

274Rg

15 ms

273Ds

02ms 0.2ms

113

Cn

278113

1.8ms

277Cn

0.6ms

275Ds

271Hs 272Hs 273Hs

~4 s

0.1 s

0.2 s

270Bh 271Bh 272Bh

61 s

267Sg 268Sg 269Sg

1.4 m

4 h

2 min

266Db 267Db 268Db

22min

265Rf

2 min

1.2 h

29 h

267Rf

?

162 164

1.3 h

276Ds

114

114

118

118

120

120

291118292118

0.5ms 0.3ms

117

295120296120

40 �s 7 �s

117

294118

1 ms

293117 294117

14 ms 78 ms

116

287116 287116288116

288116

116 0.4ms 2 ms

290116 290116 290116 290116 291116 291116292116

292116 293116 293116

29 7 ms

18 ms 18 ms 61ms

115

287115 288115289115

290115

115 32 ms 87 ms 0.22 s 16 ms

283114284114285114

286114 286114287114

287114288114

289114

0.3ms 0.5ms 0.1 s 0.13 0.36 s

0.48 5 ss

0.69 s 2.1 s

283113 284113 285113286113

0.10 s 0.48 s 5.5 s 20 s

176

279Cn 280Cn 281Cn 282Cn 283Cn 284Cn 285Cn

02 0.2ms 03 0.3ms

0.1 s

278Rg 279Rg 280Rg 281Rg 282Rg

4.2ms 0.17 s 3.6 s

277Ds

01ms 0.1ms 03ms 0.3ms 6ms 6 ms

274Mt 275Mt 276Mt

0.45 s 9.7ms 0.72 s

9.8 s

271Sg

1.9 m

270Db

23 h

166

275Hs

0.19 s

274Bh

0.9 m

279Ds 279Ds

03s 02s 0.3 0.2 s

278Mt

7.6 s

277Hs

3 ms

0.8ms 3.8 s

26 s

168 170

0.5 s

281Ds 279Ds

03s 0.3 13 s

99ms

172

29 s

174

SF

Ch.E. Düllmann – FIAS Colloquium – FIAS Frankfurt, Germany – October 20, 2011

�

� +

EC

E120 Chain Data: A. Sobiczewski et al. priv. comm.

(arb. units)

Energy E

Getting ready for element 120 at TASCA

A new digital data acquisition system for �s-isotopes

�s isotopes

Test reaction: 176 Yb( 48 Ca,4n) 220 Th

E EVR ~21 MeV

�( 220 Th)=4.9 �s

E E��=9.35 935MMeV V

E ��=8.79 MeV

�( 216 Ra)=0.9 �s

Rn 212

23.9 m

� 6.26

�

Ra 216

0.18 �s

�� 935 9.35

Lifetimes down to about 100 ns

can be measured

Time (10 ns/ch)

Experimental Electronics Dept. (N. Kurz, ...); Dirk Rudolph (U Lund)

L.G. Sarmiento

��

Th 220


9.7 �s

� 8.79

�

SHE chemistry

Hottest topic: chemistry of element 114


The Periodic Table and Relativity

1 18

1 2

H 2 13 14 15 16 17 He

3 4 5 6 7 8 9 10

Li Be B C N O F Ne

11 12 13 14 15 16 17 18

NNa MMg 3 4 5 6 7 8 9 10 11 12 Al Si P S Cl AAr

19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr

37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54

Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe

55 56 57+* 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86

Cs

87

Ba

88

La

89+"

Hf

104

Ta

105

W

106

Re

107

Os

108

Ir Pt Au Hg

112

Tl Pb Bi Po At Rn

Fr Ra Ac Rf Db Sg Bh Hs 109 110 111 Cn 113 114 115 116 117 118

Mt Ds Rg --- --- --- --- --- ---

* 58 59 60 61 62 63 64 65 66 67 68 69 70 71

Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

" 90 91 92 93 94 95 96 97 98 99 100 101 102 103

Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr

Examples of non-relativistic orbitals

s p d f



1 18

1 2

H 2 13 14 15 16 17 He

3 4 5 6 7 8 9 10

Li Be B C N O F Ne

11 12 13 14 15 16 17 18


19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36


37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54


55 56 57+* 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86

Cs

87

Ba

88

La

89+"

Hf

104

Ta

105

W

106

Re

107

Os

108

Ir Pt Au Hg

112

Tl Pb Bi Po At Rn


Mt Ds Rg --- --- --- --- --- ---

Examples of relativistic orbitals

p1/2 p 3/2

s p d f

RRelativity l ti it in i Chemistry Ch i t

Electrons near nucleus:

v is a large g fraction of c

� relativistic mass increase

1) Direct relativistic effect:

*

"

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

68

Er

100

Fm

69

Tm

101

Md

70

Yb

102

No

71

Lu

103

Lr

s and d p1/2 orbitals bit l are

stabilized / contracted

Rel. effects ~Z

2) Indirect relativistic effect:

2 � Pronounced in heavy elements

-the color of Au:

Au: �E (5d conduct. band � Fermi): 2.4 eV (in vis)

Ag: g �E (4d ( conduct. band � Fermi): ) 3.5 eV (in ( UV) )


Other orbitals (p3/2, d, f) are

better shielded from nucleus

� ddestabilized t bili d / expanded d d

-the "inert pair" effect: stabilized 6s electron pair

reduces valency: Tl(I), not Tl(III); Pb(II), not Pb(IV),...

-high ox.states of light actinides: expanded 5f orbitals

available for chemical bonding: U(VI) [but no Nd(VI)]

3) Spin-orbit splitting:

Heavy atoms: two states per l

� p1/2/p3/2; d3/2/d5/2; f5/2/f7/2 Ch.E. Düllmann – Superheavy element research – FIAS Colloquium – Frankfurt Institute for Advanced Studies, Frankfurt – October 20, 2011


1 18

1 2

H 2 13 14 15 16 17 He

3 4 5 6 7 8 9 10

Li Be B C N O F Ne

11 12 13 14 15 16 17 18


19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36


37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54


55 56 57+* 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86

Cs

87

Ba

88

La

89+"

Hf

104

Ta

105

W

106

Re

107

Os

108

Ir Pt Au Hg

112

Tl Pb Bi Po At Rn


Mt Ds Rg --- --- --- --- --- ---

* 58 59 60 61 62 63 64 65 66 67 68 69 70 71

Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

" 90 91 92 93 94 95 96 97 98 99 100 101 102 103

Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr

Rel. effects ~Z2 Element 114, � member Pronounced in group in heavy 14: elements

-the -Electronic color of Au: conf.: [Rn] 7s

Au: �E (5d conduct. band � Fermi): 2.4 eV (in vis)

Ag: �E (4d conduct. band � Fermi): 3.5 eV (in UV)

2 6d10 5f14 7p 2

1/2

-"Quasi-closed g ( shell" configuration g ) due ( to )

relativistic p

-the "inert pair" 1/2 subshell closure

effect: stabilized 6s electron pair

reduces Evident valency: question: Tl(I), not Tl(III); Pb(II), not Pb(IV),...

-high metallic t ox.states lli (Pb (Pb-like) lik of light )bbehavior, actinides: h i or expanded 5f orbitals

available noble-gas for (Rn-like) chemical bonding: behavior? U(VI) [but no Nd(VI)]

Examples of relativistic orbitals

p1/2 p 3/2

s p d f

RRelativity l ti it in i Chemistry Ch i t

Electrons near nucleus:

v is a large g fraction of c

� relativistic mass increase

1) Direct relativistic effect:

s and d p1/2 orbitals bit l are

stabilized / contracted


Other orbitals (p3/2, d, f) are

better shielded from nucleus

� ddestabilized t bili d / expanded d d

3) Spin-orbit splitting:

Heavy atoms: two states per l

� p1/2/p3/2; d3/2/d5/2; f5/2/f7/2 Ch.E. Düllmann – Superheavy element research – FIAS Colloquium – Frankfurt Institute for Advanced Studies, Frankfurt – October 20, 2011

Chemical Theory on Element 114

(a small selection)

1975: Pitzer: "Are elements 112, 114, and 118 relatively inert gases?" [1]

Recent fully relativistic quantum chemical calculations:

Solid-state calculations [2]: Cn resembles group 12 metals more closely

than the noble gases

Solid-state calculations [3]: E114 more weakly bound than Pb and Hg;

spin-oirbit effects lead to chemical inertness (along the lines of Pitzer)

Calculations on MM-M M' interactions (M=Cn; E114; M'=metal M=metal, ee.g., g Au) [4 [4-6]: 6]:

M-M' NOT of VAN DER WAALS type, should reveal a metallic character:

For Cn due to the 7s and 6d 5/2 AOs

For E114 due to 7p 1/2 and 7p 3/2 AOs

�Element 114 expected to be a rather inert, volatile metal

[1] K.S. Pitzer, J. Chem. Phys. 63, 1032 (1975).

[2] N. Gaston et al., Angew. Chem. Int. Ed. 46, 1663 (2007).

[3] A. Hermann et al., Phy. Rev. B 82, 155116 (2010).

[4] V. Pershina, Radiochim. Acta, 99, 459 ( (2011). )

[5] V. Pershina et al., J. Chem. Phys. 131, 084713 (2009).

[6] A. Zaitsevkii et al., Russ. Chem. Rev. 78, 1173 (2009).


(Relativistic) Energy of Valence Orbitals

E , eV

-5

-77

-9

-11

-13

-15

-17 17

-19

s s1/2 1/2

Hg

112

Tl

p p1/2 1/2

113

Pb

114

115

Bi

116

p p3/2 3/2

117

7p3/2

118

6p3/2

6p1/2

7p1/2

-21

11 12 13 14 15 16 17 18 Group 19

V. Pershina et al., J. Chem. Phys. 132 (2010) 194314

s 2 p 1 p 2 p 1 p 2 p 3 p 4

s 2

1/2 p1/2

1

p1/2

2

p3/2

1

p3/2

2

p3/2

3

p3/2

4

Vl Valence El Electrons t


12

13

14

6s

-7 eV

6p 1/2

-3.0 eV

6p 1/2

-4.2 eV

M-Au Bonding (Dimer)

��

�

HgAu 112Au D e (eV)

D e (eV)

��

�

��

6s

-66 eV

0.67

7s

-9.7 eV

TlAu 113Au

6s

-6 eV

2.72

7p 1/2

-4.0 eV

PbAu 114Au

6s

2.15

��

�

��

�

��

6s

-6 eV

6s

-6 eV

� -6 eV

-5.3 eV � -6 eV

6s

0.51

1.83

7p 1/2 0.73

155 BiAu 2.62

115Au 2.52

E114-Au bond is stronger than E112-Au!!

V. Pershina et al.,

J. Chem. Phys. 133 (2010) 104304


Simulation of M Adsorbed on Au(100)

Clusters MAu

top hollow

n=14 n=9

bridge

Embedded cluster MAu MAunAu Aum

ad-atom

cluster l t

environment

n = 16 n = 34-36 m = 156

Increase cluster size until convergence g is reached � M-M' dimer trends preserved! p

Interaction E114 – Aun is stronger than Cn – Aun V. Pershina, "Electronic Structure and Chemistry of the Heaviest Elements" in Relativistic Methods for Chemists; Eds: Leszczynski/Ishikawa; Springer (2010) 451


Production of elements 112 and 114

238 U( 48 Ca,3n)

Z

112

112

110 110 Ds

confirmed at TASCA!

244Pu( 48Ca,3-4n) 242Pu( ( 48Ca,3n) , )

112

279Ds 279Ds

0.2 s

N

114

114 114

286114 286114 286114 286114 286114 287114 287114 288114 288114 289114 289114

0.36 0.13 0.36 0.13 0.36 0.13 0.36 0.13 s

s 0.5 s 0.8 s 2.7 s

282112 282112 283112 283112 284112 284112 285112 285112

0.8ms 3.8 s 0.1 s 34 s

281Ds 281Ds

9.6 s

170 170 172

172

174

174


��

SF

Experimental approach:

Testing interaction "E114 E114 �� Au" Au

Isothermal Gas Chromatography

Temperat T ure [°C]

Temmperaturee

[°C]

Gas flow

Column lengths [cm]

Rel. Yieeld

[%]

T 50%

Thermochromatography g p y

Gas flow

Column length [cm]

Rel. Yieldd

[%]

t Ret.=T 1/2

low Temperature [°C] high

T a

high Temperature [°C] low


Previous study: Volatility and reactivity of Hg, Rn, Cn, and E114

R. Eichler et al., Radiochim. Acta 98 (2010) 133

Element -�H �Hads d

Hg ≥50 kJ/mol

Rn 19 kJ/mol

Cn (Z=112) 52 kJ/mol

287 114 34 kJ/mol

288 114 34 kJ/ kJ/mol l

+20

E114 (68%): 34 -3 kJ/mol

+54 54

(95%): 34 -11 kJ/mol

Theory Experiment

Pb > 114 �� Hg > 112 Hg > 112 > 114

The TASCA Element 114 Chemistry Collaboration

TU MMunich nich (D) AA. Yak Yakushev she (collaboration spokesperson)

J.M. Gates, A. Gorshkov, R. Graeger, A. Türler

GSI Darmstadt (D) D. Ackermann, M. Block, W. Brüchle, Ch.E. Düllmann, H.

Essel, J.M. Gates, W. Hartmann, F.P. Heßberger, A. Hübner,

E. Jäger, J. Khuyagbaatar, B. Kindler, J. Krier, N. Kurz, B.

Lommel, J. Runke, M. Schädel, B. Schausten, E. Schimpf,

JJ. Steiner

Univ. Mainz (D) Ch.E. Düllmann, K. Eberhardt, M. Eibach, J. Even, D. Hild,

J.V. Kratz, L.J. Niewisch, P. Thörle-Pospiech, N. Wiehl

HIM Mainz (D) Ch.E. Düllmann, F.P. Heßberger

Univ. Liverpool (UK) L.-L. Andersson, R.-D. Herzberg, E. Parr

LBNL/UC Berkeley (USA) J. Dvorak, H. Nitsche

Univ. Lund (S) U. Forsberg, D. Rudolph

Univ. Oslo (N) J.P. Omtvedt, A. Semchenkov

IMP Lanzhou (PRC) Z. Qin

U Jyväskylä J. Uusitalo

ITE Warsaw (PL) M. Wegrzecki



TASCA

Preseparator: clean samples available for transport

TASCA – COMPACT 2 configuration for the study of element 114 chemistry

Element 114

Trajectory

TASCA: M. Schädel, EPJD 45 (2007) 67; A. Semchenkov et al., NIMB 266 (2008) 4153, J. Gates et al., PRC 83 (2011) 054618

TASCA Preseparator: Ch.E. Düllmann, Radiochim. Acta 99 (2011) 515; J. Even et al., NIMA 638 (2011) 157; J.P. Omtvedt et al. (to be publ.)

COMPACT J. Dvorak et al., PRL 97 (2006) 242501; PRL 100 (2008) 132503



TASCA

Preseparator: clean samples available for transport

TASCA – COMPACT 2 configuration for the study of element 114 chemistry

Element 114

Trajectory

COMPACT I

Isothermal Chromatography (IC)

Metals

(e.g., Pb; Hg)

+21°C 21 C

COMPACT II

Thermochromatography (TC)

Cn

Rn...

+21°C

-162°C

TASCA: M. Schädel, EPJD 45 (2007) 67; A. Semchenkov et al., NIMB 266 (2008) 4153, J. Gates et al., PRC 83 (2011) 054618

TASCA Preseparator: Ch.E. Düllmann, Radiochim. Acta 99 (2011) 515; J. Even et al., NIMA 638 (2011) 157; J.P. Omtvedt et al. (to be publ.)

COMPACT J. Dvorak et al., PRL 97 (2006) 242501; PRL 100 (2008) 132503


Experimental setup: IC + TC

COMPACT2 COMPACT @ TASCA

RTC

COMPACT CO COMPACT AC I ( (@ room temp) )

COMPACT

COMPACT II

(+21 to ‐160 160°C) C)

A. Yakushev, 2010


Summary

Superheavy elements:

Elements up p to Z=118 reported; p up p to 112 and 114/116 approved pp

Location of next spherical shell closure still unclear

Research at GSI/U Mainz: Unique combination of facilities

HIM: A new SHE condensation nucleus

Toward a dedicated SHE Linac (together with IAP Frankfurt)

TASCA TASCA: TASCA TASCA: highest efficiency for hot fusion reactions: 60%

Physics @ TASCA TASCA: 50Ti+ 249Cf � element 120 ended last week

Chemistry @ TASCA TASCA: TASCA TASCA: E114!


Superheavy Element Research Superheavy Element Research

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