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 



Liu 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 



Liu 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 

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

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 


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 



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 


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 



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 

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

�� 

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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