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FIFTY YEARS IN ION CHEMISTRY FIFTY YEARS IN ION CHEMISTRY
WITH COLLEAGUES AND FRIENDSWITH COLLEAGUES AND FRIENDS
ZDENEK HERMANV.Čermák Laboratory,
J. Heyrovský Institute of Physical Chemistry,
Academy of Sciences, Prague
Gordon Research Conference “Gaseous Ions”, Galveston, Keynote Lecture,, March 5, 2009
(Mann et al 1940) - Talroze 1952 - Stevenson, Schissler 1955-56 – Field, Franklin, Lampe 1957
THE FIRST TRY (July 30, 1958)
INSTITUTE OF PHYSICAL CHEMISTRY, ACADEMY OF SCIENCES, PRAGUE
1959-60 REACTIONS OF ELECTRONICALLY EXCITED REACTANT IONS
( in N2, O2, CO, CO2, COS, CS2)
A.E. =21.7 eV
N2+*(4Σu) + N2(1Σg
+) → N3+(3Σg
-) + N(4S)
• very small apparent cross section • A.E.(N3
+) higher than IE(N2)
• reaction endothermic with g.s. reactants
• exothermic only with electronically excited N2
+*
N2+*(4Σu) – theoretically predicted
but not yet detected
V. Čermák, Z. Herman, J. Chim. Phys., 1960
Vladimír Čermák
1962-63ASSOCIATIVE AND PENNING IONIZATION
Kinetics of reactions in mixtures with metal vapors: Hg, Li, Na, K, Cs
Ion-molecule reactions
Associative ionization (excited neutral + A ,M)
Ar*m + Hg → ArHg+ + e
He*m + Li → HeLi+ + e
Kr*m + Cs → KrCs+ + e
Ar*m + C2H2 → ArC2H2+ + e
ION SOURCE WITH MOLECULAR BEAMS
Penning ionization
R*m + ABC → R + ABC+ + e
→ R + AB+ + C + e
→ R + A+ + BC + e
• mass spectra of product ions
• deposition of energy from R*m
Penning ionization electron spectroscopy
(V. Čermák)
•precise measurements of the energy of released electron
C3H8
DYNAMICS OF ION-MOLECULE REACTIONS
YALE 1964 – 65
(Richard Wolfgang)
construction of EVA I
(crossed-beam scattering machine)
Reactive scattering of neutrals in beams (1961-64)
[S.Datz, E.H Taylor (1955)] - D.R. Herschbach et al. –
E.F. Green, J. Ross – R.B. Bernstein
C2H4+ + C2H4 → [C4H8
+] → C3H5+ + CH3
DYNAMICS OF ION-MOLECULE REACTIONS
DISTINGUISHING COLLISION MECHANISMS BY SCATTERING
New Haven, Boulder 1964 - 69
DIRECT MECHANISM (STRIPPING)
• even at quasi-thermal energies
• polarization stripping
INTERMEDIATE COMPLEX FORMATION
• angular scattering
• translational energy distribution
• lifetime of complexes
B. Mahan – A. Henglein - Champion, Doverspike
THE COMPLEX MINUET
(to which Dudley Herschbach wrote the tune)
SPECTATOR STRIPPING
REACTION MECHANISMS
1970 - 1982DYNAMICS OF ION-MOLECULE PROCESSES
Prague, after 1969
EVA II
(with V. Pacák)
H2+(v) + He → HeH+ + H
Experiments: V. Pacak, Z. Herman, K. Birkinshaw (Prague)
Trajectory calculations: F. Schneider, U. Havemann, L. Zülicke (Berlin)
ANGULAR TRANSLATIONAL VIBR ROT OVERALL ENERGY
F.Schneider, U. Havemann, L. Zulicke, V. Pacak, K. Birkinshaw, Z. Herman, Chem.Phys.Lett. 37 (1976) 323
DYNAMICS OF ION-MOLECULE PROCESSES
Ar+ + H2 → Ar + H2+
CHARGE TRANSFER
H+- transfer complex H-atom transfer
CH4+• + CH4 → CH5
+ + CH3•PARALLEL MECHANISMS
DYNAMICS OF ION-MOLECULE PROCESSES
V. Pacák - K. Birkinshaw – A. Yencha – J. Futrell – P. Hierl – M. Henchman – B. Friedrich – J. Vančura
1983 -DYNAMICS OF REACTIONS OF DICATIONS
Ar2+(3P ) + He
He2+ + NO → He+*(2P) + NO+(1Σ+, v)
13CO2++ 12CO 13CO+ (B2Σ+) + 12CO+(A2Π)
13CO+ (A2Π) + 12CO+(B2Σ+)
CHEMICAL REACTIONS
CF22+ + D2 → CF2
+ + D2+
→ CF2D+ + D+
PRODUCT LUMINESCENCE
CHRISTOPH
OTTINGER
Collaboration: B. Friedrich, J. Vančura, M. Sadílek, Z. Dolejšek, M. Fárník, L. Mrázek, J.
Žabka, J. Roithová
5 10 15
1E-3
0.01
0.1
1
10
HOPG Heatedy = (5.4±1.1) + (-0.5±0.1).x
y = (3.9±0.5) + (-0.39±0.04).x
C2H+
4
C2H+
2
CD+
3
CD+
4
C2H+
3
C2H+
5
CD+
5
Sa
[ % ]
IE [eV]
N2
+
HOPG Room Temp
5 10 15
1E-3
0.01
0.1
1
10
Be - Room T
C3H+
8
C3H+
7
C3H+
3
C3H+
5CD+
5
CD+
4
N+
2
Ar+ HOPG W Be
CO+
2
C2H+
4
C2H+
2
C3H+
6
CD+
3
CD+
4
C3H+
8C
3H+
4
C2H+
3
C2H+
5
C3H+
5
C3H+
3
C7H+
8C
3H+
7
CD+
5
Sa
[ % ]
IE [eV]
C7H+
7
Ar+
HOPG - Room T
W - Room T
1998 -ION - SURFACE COLLISIONS
0 5 10 15 20 250
25
50
75
100
0 5 10 15 20 250
25
50
75
100
0 5 10 15 20 250
25
50
75
100 E'int
E'tr
E'surf
P(E
')P
(E')
CH-SAM
P(E
')
0.30
0.06
0.64
0 5 10 15 20 250
25
50
75
100
E' [eV]
E'int
E'tr
E'surf
=60o, Einc
=21-22eV
CF-SAM
0.46
0.370.17
E'int
E'tr
E'surf
0.660.280.06
P(E
')
HOPG
E'int
E'tr
E'surf
0.06
0.32 0.62
CH/SS
ENERGY PARTITIONING
ION SURVIVAL IN SURFACE COLLISIONS
SURFACE COLLISIONS OF CLUSTER IONS
INNSBRUCK (1998 - )
collaboration with Tilmann Märk et al.
CH/C(HOPG)
log Sa = a – b (IE)
COLLEAGUES COLLEAGUES AND AND
FRIENDSFRIENDS
www.jh-inst.cas.cz, personal pages - ZH
Farewell to Mike Menzinger 1969
(Mike Menzinger, Jim Kerstetter, Jim Richardson, John Krenos, Pete Hierl,
Rod LeRoy, Dick Wolfgang, John Hawke, Andy Yencha,
Zdenek Herman, Al Lee, Cal Blakely)
BOULDER
JILA A.D. 1980
JILA 1980: Carl Lineberger holding the reinsJILA 1980: Beards and hairs of Steve Leone’s group.
JILA 1980: The FAIR (flowing-afterglow infra-red) people:Barney Ellison, Mark Smith, Tim Zwier, Jim Weisshaar,
Veronica Bierbaum, Zdenek Herman
CU – Chemistry 1980:
Eldon Ferguson watching the flow-tube centersCU – Chemistry 1980: Will Castleman
CU – Chemistry 1980: Chuck DePuy CU – Chemistry 1980: Barney Ellison
Dudley Herschbach (Harvard) in the center of mass
Yuan T. Lee A.D. 1998
(Berkeley and Taipei)
U.S.A.
Steve Berry, Chicago Ugo Fano, Chicago
The Research Director (Graham Cooks)
Mike Henchman, Brandeis Jean Futrell at SASP 04
Peter Toennies (Göttingen) and Giorgio Benedek (Milano)
struggling with the surface lattice dynamics
GÖTTINGEN
Christoph Ottinger, Göttingen
Jürgen Troe (Göttingen)Evgenii Nikitin (Moscow, Haifa)
Tilmann Märk Werner Lindinger
INNSBRUCK
OKAZAKI
Saburo Nagakura Hiroki Nakamura
Inosuke Koyano
Tamotsu Kondow
EUROPEAN NETWORKS
SRMIon Network: Paul-Marie Guyon , Orsay MCINet: Davide Bassi and Paolo Tosi, Trento
Dieter Gerlich, Chemnitz Odile Dutuit, Orsay
Diethard Böhme, Toronto Helmut Schwarz, Berlin
Franco Gian-Turco (Rome)
Victor Sidis, Orsay The two Gentlemen of Madrid:
Gerardo Delgado-Barrio and Pablo Villarreal
MOLEC PEOPLE
Enzo Aquilanti, Perugia
GORDON RESEARCH CONFERENCE , 1964
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