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