interaction of trapped ions with light mo 30.05 · hlavova 2030/8, ch5 discussions: beer garden of...

30. and 31 May 2016: Lecture series

Prof. Dieter Gerlich Charles University in Prague, Faculty of Science, Department of Organic Chemistry

Mo 30.05.2016 10:00-12:00

Hlavova 2030/8, CH5

Lecture 1

RF technology: Charged particles in inhomogeneous rf fields Motion of ions in fast oscillatory fields Introduction, motivation, electrostatics, ion optics, development of the theory, adiabatic approximation

Special field geometries Electrode arrangements, Laplace equation, two dimensional multipoles, energy distributions, technical hints

Selected instruments and basic applications Quadrupole MS (history, Mathieu Equations, stability), instruments using ion guides and traps

Mo 30.05.2016

13:00-15:00 Hlavova 2030/8, CH5

Lecture 2

Interaction of trapped ions with light Summary first lecture Magic numbers

Laser fragmentation, laser induced processes Fragmentation in fast ion beams, laser induced reactions, NPMS, laser heating of C60

+

Laser cooling, ultracold atoms and molecules, chemistry below 1 K? Sub-K world, energy and impulse of a photon, cooling with light, atomic clocks

Recent progress in spectroscopy in cryogenic ion traps IR spectra of H3

+ and He-H3+, first laboratory detection of DIBs

Di 31.05.2016 15:00-17:00

Hlavova 2030/8, CH5

Discussions: beer garden of Husa

Astrochemistry Reactions in the early universe Physical conditions, available elements, observations

Hydrogen in the universe H and H2: basics, from H- to H21

+, laboratory studies of collisions with H-atoms

Laboratory experiments to understand our "chemical history" Molecules detected in space, isotope enrichment, formation of hydrocarbons

Recent results from ISORI Iron in space

D. Gerlich 30. 05. 2016

30.05.2016

Prof. D. Gerlich

RF technology: Charged particles in inhomogeneous rf fields

Introduction My scientific life, motivations A few projects

Motion of ions in fast oscillatory fields Electrostatics, ion optics Development of the theory Adiabatic approximation

Special field geometries, electrode arrangements Electrode arrangements Laplace equation Two dimensional multipoles Energy distributions Technical hints

Selected instruments, basic applications Quadrupole MS (history, Mathieu equations, stability) Instruments using ion guides and traps Simple applications

Universität Fakultät für NW

Professur Ionenphysik (1994 - 2009)

IonenphysikProf. Dr. Dieter GerlichFormer coworker

Lectures PragueResearch

Prague ISORIBaselKölnPrague AB-22PT

Publicationsinvited talks

Selected conferences

On 01. Feb. 1994 Prof. D. Gerlich took over the group Gasentladungs- and Ionenphysik. In addition to the traditional studies ofdischarges (e.g. polymerization, etching) various fundamental laboratory studies have been started. The aim was to understand indetail all kind of plasmas, ranging from technical applications to astrochemistry. Developing innovative ion guides and lowtemperature ion traps and combining them with lasers, molecular beams, sophisticated detectors etc., many unique experimentalstudies became possible.

Since his retirement (30.09.2009), Prof. D. Gerlich is actively engaged in several laboratories in Prague, Basel, Köln and otheruniversities. Of central importance are applications of new cryogenic traps in reaction dynamics and spectroscopy.

Research activitiesIOTA Ion Traps for TomorrowsApplicationsITS LEIF Low Energy Ion BeamFacilitiesThe Chemical CosmosFGLA Laboratory astrophysics

Cryogenic s4PT: new results for C60+ and C70

+

E. K. Campbell, M. Holz, J. P. Maier, D. Gerlich,G. A. H. Walker, and D. Bohlender

Gas phase absorption spectroscopy of C60+ and C70+ in a cryogenic ion trap:comparison with astronomical measurements

Ap. J. 822 (2016) 17-24

See also Nature, 523 (2015) 322 DOI: 10.1038/nature14566

Left: For heavy ions in helium, a cryogenic linear quadrupole is especially well suitedfor determining absolute photo absorption cross sections. The ion cloud (red) iscompletely embedded in the laser (yellow). For more details see [jas15]

Dieter Gerlich 16.05.2016

Education1971 Diplom, Albert-Ludwigs-Universität Freiburg 1977 Promotion, Albert-Ludwigs-Universität Freiburg 1978-1979 Postdoc Prof. Y. T. Lee, University of California, Berkely 1989 Habilitation (06.07.89), Venia Legendi (12.07.89) Albert Ludwigs-Universität Freiburg

Academic appointments 1971-1978 Scientific employer, Albert Ludwigs-Universität, Freiburg 1978-1979 DFG fellowship, Postdoc, University of California, Berkely 1979-1993 Hochschulassistent (C1) 1989 Privatdozent, Albert Ludwigs-Universität Freiburg 1994-2009 Full professor (C4), Technische Universität Chemnitz, emeritus 1995-1997 Director, Institute of Physics, TU Chemnitz 1998 Guest Professor Institute of Atomic and Molecular Science, Taipeh 2000 - 2006 Speaker of the DFG "Forschergruppe "Laboratory astrophysics 2006 - 2011 Professor of Chemistry, Univ. of Arizona, adjunct appointment 2009 - 2010 Professor, Charles University in Prague since 2011 Several active cooperations (Basel, Köln, Prague, Salt Lake City)

1969 First octopole, first storage ion source

Dieter Gerlich, Dipl. Arbeit, Uni Freiburg

History: guided and trapped ions

D. Gerlich, J. Anal. At. Spectrom., 19, (2004) 581

1970

1978

1985

1978-79 First Guided Ion Beam with VUV PI

S.L. Anderson, F.A. Houle, D. Gerlich, and Y.T Lee J. Chem. Phys. 75 (1981) 2153

TU Chemnitz

FGLA Forschergruppe Laboratory Astrophysics

2000 - 2006 FSU Jena

Research unit 388 Structure, dynamics and properties of molecules and grains in space

Sprecher: Prof. Dieter Gerlich, TU Chemnitz

Final report (Jan 2007)

Projects 2003 -2006 Projects 2000 -2003 Project leaders Aim (2000) Guests Publications Links Contact

Special book (in preparation)

From 2000 to 2006 the Deutsche Forschungsgemeinschaft has supported the Forschergruppe Laboratory Astrophysics: Structure, Dynamics and Properties of Molecules and Grains in Space, briefly called FGLA. Laboratory astrophysics and astrochemistry belongs to an in-terdisciplinary research area covering the physics and che-mistry of molecules, clusters, nanoparticles, and grains under the conditions of interstellar space, ranging from low tempera-ture and low density molecular clouds to hot environments of stars. It was our aim to study the microphysics which control the formation and destruction of interstellar matter and to use the results for understanding observational facts and for pre-dicting new astrophysical features. The final report (Jan. 2007) reveals that the theoretical and experimental projects have made major contributions to the field of laboratory astrophysics and -chemistry: worldwide, the FGLA has become an attractive center in its field. We thank our universities and institutions for their help and especially the DFG for the generous financial support.

D. Gerlich 05.12.2008

The Lausanne cooled ion spectrometer

O. Boyarkin, S. Mercier, A. Kamariotis, and T. Rizzo J. Am. Chem. Soc.; 128 (2006) 2816

Electronic spectra: the Basel 22PT

A. Dhzonson, J.P. Maier Electronic absorption spectra of cold organic cations: 2,4-Hexadiyne. Int. J. Mass. Spec. 255 (2006)139

one photon dissociation spectrum 30 K 300 K

Quo vadis?

Grand Canyon 2006

Transfer 22PT -> Prague

buffer gas cooling ultracold ions: N2

+

01.10.2009

Reactions with H atoms

Neg ions

H- + H

Ion Spectroscopy of Reaction Intermediates (ISORI)

J. Jašík, J. Žabka, J. Roithová, D. Gerlich

Prof Jana Roithová Charles University in Prague

ERC starting grant: begin Jan 2011

TSQ 7000

ION SPECTROSCOPY OF REACTION INTERMEDIATES

30.05.2016

Prof. D. Gerlich






Ion optics

Electric field manipulation Electrostatic lens Einzel lens Electrostatic analyzer Quadrupole deflector

Magnetic field manipulation Magnetostatic lens Mass-to-charge ratio Mass spectrometry

SimIon http://www.simion.com/

Electrostatic einzel lens

Ions in static or quasiIons in static or quasi--static electrostatic electro--magnetic fieldsmagnetic fields

q = electric charge

B = magn. induction

E = electric field

v = velocity

Lorentz Force (1)

For ion acceleration electric forces are used.

For momentum analysis the magnetic force is preferred because the

force is always perpendicular to B. Therefore v, p and E are constant.

Force in magnetic dipole B = const: p = q B p = mv = momentum

= bending radius

= magn. rigidity

Dipole field B

perpendicular

to paper planeRadius

Object (size x0)

General rule:Scaling of magnetic system

in the linear region results

in the same ion-optics

Note: Dispersion x/ p

used in magnetic analysis,

e.g. Spectrometers, magn.

Separators,

x

p

p+ p

4

The BrowneThe Browne--BuechnerBuechner,,

a Historic Spectrographa Historic Spectrograph

built at MIT (1951built at MIT (1951--1954)1954)

Spectrograph refers to an

instrument with a photographic

plate (historic!) in the focal plane

Spectrometer refers to an electrical

detection system in the focal plane,

e.g. a postions sensitive wire

chamber

17

TheThe WienWien FilterFilter

1,813kV/mm 0.3 T

B Field linesGradient of

E Field lines

Units in mm

(1)

F = 0 when qE = qv x B with E

(19)v = E/B with E

Design study of

Wien Filter

for St. George

Electrostatic system of

Danfysik Wien Filter

20

Grand Raiden High Resolution SpectrometerGrand Raiden High Resolution Spectrometer

Beam Line/Spectrometer fully matchedMax. Magn. Rigidity: 5.1 Tm

Bending Radius: 3.0 m

Solid Angle: 3 msr

Millikan´scher Öltröpfchenversuch

Phys. Rev. 2 (1913) 109

Kräfte: Elektrostatische Kraft

Schwerkraft Auftrieb Reibung

Das Geonium

Scientific American 1980

30.05.2016

Prof. D. Gerlich






Advances in Chemical Physics, LXXXII, J. Wiley & Sons (1992)

I. Introduction II. Motion of Charged Particles in Fast Oscillatory Fields III. Experimental Applications and Tests of Several rf Devices IV. Description of Several Instruments V. Studies of Ion Processes in RF Fields: A Sampling VI. Conclusions and Future Developments

Development of the theory Thomson (1903) X-ray scattering cross section, classical non-relativistic motion of an electron in the field of a plane electromagnetic wave Equation of motion

q, m: charge and mass of the electron E0 peak electric field vector

Ω angular frequency

Kapitza and Dirac (1933) high light intensities: stimulated photon interactions: ponderomotive effect. optical standing wave can scatter electrons Kapitza (1951) quasipotential, ponderomotice potential, pseudopotential, effective potential (1961 textbook by Landau and Lifshitz) 1960ies development of the laser Many experiments

Nuclear fusion reactor

Problem in the 1950s: isolate a plasma from walls Weibel (1959) Linhard (1960), review Motz and Watson (1967) two- and three-dimensional potential wells with oscillatory fields

stability conditions Confinement of both electrons and ions in a neutral plasma effective potential is independent of the sign of the charge

V* ~ q2 Superimposed fields at different frequencies Gapanov and Miller; 1958 compressing simultaneously electrons and ions as well as plasma heating

Electron beam guide

Weibel and Clark (1961)

20-cm-long circular, properly terminated wave guide (cavity) Ω/2π = 9.29 GHz, 250 kW of rf power, 2 ps pulses axis: nodal line of the microwave field = locus of a two-dimensional effective potential minimum. Peak electrical field: 52 kV/cm Adiabatic theory (effective potential for electrons): V*=400 eV Frequency of the secular motion 0.033 Ω, corresponding to: η < 0.1

Motion in a fast oscillating field

Kapitza 1951, Landau-Lifschitz Classical Mechanics 1962

Fast oscillation: Landau - Lifshitz

Effective potential and micromotion

Trajectory 8pole: conservation of L

Bewegung in einem 32-Pol

Different initial conditions

30.05.2016

Prof. D. Gerlich






Linear quadrupole

Confinement of charged particles in rf or AC fields

30.05.2016

Prof. D. Gerlich


Laplace equation

No space charge

ΔΦ = 0

space charge ρ

ΔΦ = -4πρ

Earnshaw-Theorem (1882)

In Systemen, die von invers quadratischen Kraftgesetzen (∝ r-2) bestimmt werden,

kann es kein lokales Minimum (oder Maxi-mum) der potentiellen Energie geben.

Potential: two concentric cylinders

Field of two line charges

RF - grid

Potential see Eq. 35 in [ger92]

( ) ( )λλ /cos)/exp(, 0 yxyx Φ=Φ

( ))/2exp(

2 22

20 λλ

xmqVVΩ

=∗

potential

effective potential

The distance between electrodes is πλ The boundary conditions can be approximated with rods with a diameter of 2λ. The effective potential is independent on y

Ion mirror!

Ring electrode traps (1990)

Ring electrode trap

w4PT: optimal geometry

J. Jasik, D. Gerlich, 12.12.2011

30.05.2016

Prof. D. Gerlich






Ion trapping in rf fields

2n-2

Non-ideal boundary conditions

Octopole, one rod off

dc distortion on one rod

Octopole with dc difference

Creation a potential barrier

30.05.2016

Prof. D. Gerlich






Energy: instantaneous and time averaged

Change of velocity Δv/v

Kinetic energy distribution

Kinetic energy distribution with collisions

30.05.2016

Prof. D. Gerlich






Quadrupole, Paul trap

Strong-focusing, alternating-gradient principle Courant (1952): A series of quadrupole fields alternating in space can confine fast beams of protons Quadrupole mass filter Paul and Steinwedel (1953), Paul and Raether (1955), Paul et al. (1958) The spatial periodicity is replaced by quasistationary fields alternating in time This leads, under suitable conditions, to a "focusing" force for low-energy ions. Three-dimensional Paul trap Fischer (1959); Wuerker et al. (1959a), Dawson (1976) Oscillating quadrupole fields very special equation of motion decoupled one-dimensional differential equations of the Mathieu type stability of a trajectory does not depend on initial conditions

Mathieu equation (a,q) diagram

1-dimensional Paul trap

QP mass spectrometer

Linear quadrupole: equation of motion

Stability Paul trap

30.05.2016

Prof. D. Gerlich






1980 - 2000 Uinversal Guided Ion Beam Apparatus

1992 first 22PT instrument

D. Gerlich J. Chem. Soc. Faraday Trans., 89 (1993) 2199 D. Gerlich Physica Scripta, T59 (1995) 256

22PT ring electrodes

Buffer gas cooling in an rf trap

Dynamic traps such as Penning, storage rings, cone trap

do not work

Paul trap does not work η = const

Only way to cool efficiently internal degrees of freedom

are rf multielectrode traps

sub K: cold pulsed effusive beam

H

e de

nsity

/ cm

-3

Reaktionen im Ionenspeicher I

Reaktionen im Ionenspeicher II

Typical measurement at 300 K: CH4+

FGLA report 2003

Injected: CH4+ , CH3

+ [H2] = 7.4 × 1010 cm-3 T = 300 K hydrogen abstraction CH4

+ + H2 →CH5+ + H

k = 3.9 ×10-11 cm3 s−1

Radiative association CH3

+ + H2 →CH5+ + hv

proton transfer to H2O

Stationary equilibrium: n = ?

Paul et al. 1995

T = 10 K, [H2] = 1014 cm-3, storage time 10 s

n-H2

p-H2

Merged beams

neutral density (cm-3) 3×1011 1×106

interaction time (µs) 35 0.27 conversion efficieny 10-2 3×10-10

velocities (km/s)

carbon beam - ionizer - ring electrode trap

I. Savic, I. Cermak, D. Gerlich, Int. J. Mass Spectrom., 240 (2005) 139

0.0 0.2 0.4 0.6 0.8 1.010-1

100

101

102

103

104

D3+ + C3 →

t / s

Ni

D3+

C3D+

C3D2+

104 105 106 107 108 10910-1

100

101

102

103

104

D3+ + C3 →

nC3

/ cm-3

Ni

D3+

C3D+

13C12C2D+

C3D2+

storage time / s [C3] / cm-3

ions

per

filli

ng

ions

per

filli

ng

30.05.2016

Prof. D. Gerlich

Interaction of trapped ions with light Summary

Trapping and applications

Laser induced processes Spectroscopy in fast ion beams Laser induced reactions Laser heating of C60

+

Laser cooling, ultracold atoms and molecules, chemistry below 1 K?

Sub-K world Energy and impulse of a photon Cooling with light, atomic clocks

Recent progress in spectroscopy in cryogenic ion traps IR spectra of H3+ and He-H3+ First laboratory detection of DIBs Results from ISORI

interaction of trapped ions with light mo 30.05 · hlavova 2030/8, ch5 discussions: beer garden of...

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