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Born Oppenheimer Näherung R pp (Kernabstand) rere Kernwellenfunktion Elektronische Wellenfunktion R nur Parameter Potential Wie sieht die Wellenfunktion.

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Präsentation zum Thema: "Born Oppenheimer Näherung R pp (Kernabstand) rere Kernwellenfunktion Elektronische Wellenfunktion R nur Parameter Potential Wie sieht die Wellenfunktion."—  Präsentation transkript:

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2 Born Oppenheimer Näherung R pp (Kernabstand) rere Kernwellenfunktion Elektronische Wellenfunktion R nur Parameter Potential Wie sieht die Wellenfunktion dazu aus? Näherung: Harmonischer Oszillator

3 Measure the internuclear distance: Reflection Approximation harmonic oszillator Morse Potential

4 E CO 1.13 Å 1.08 Å CO +(C1s) 300meV h Elektronenenergie

5 Molecular Innershell Photoionization – fixed in space molecules C O C O h = 295 eV e - from K-shell, 10eV Energy molecular orientation measurement Polarization

6 Molecular Innershell Photoionization – fixed in space molecules h = 295 eV Photoelectron (10eV) C O C O Auger Electron 250 eV C O CO C O + +

7 Electric field Detector Dead Time (10nsec) CO: Carbon K-Ionization

8 CO 2+ CO eV photon CO + ground state Photoelectron Auger Electron Franck-Condon for C-K Hole (B-State) C + ( 2 P)+O + ( 4 S) From: Kerkau and Schmidt

9 Axial Recoil Approximation: is the Fragmentation faster than Rotation?

10 Identical fit !

11 rotation angle 50deg O C random rotation with exponential distribution of rotation angle

12 rotation angle 50deg O C random rotation with exponential distribution of rotation angle

13 Osipov et al PRL 90(2003) femto second clock Acetylene HCCH HC + Vinylidene C+C+ H2C+H2C+

14 Osipov et al PRL 90(2003) Physics Today Aug.2003 p 19ff Isomerization Time? 0.35 rad Mean angle of rotation Fit randomly rotated A pattern to V measurements <60 fsec

15 O C Polarization Interference between different classical paths (diffraction pattern) h He + 99eV -> He 1+ (1S) + e -

16 O C Polarization Interference between different classical paths (diffraction pattern) h h = 295 eV + L = 1 (within dipole approximation) Entangled State of rotating Molecule and Electron

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18 O C h O C h

19 O C h O C h

20 Chirality in Nonmagnetic Systems? initial state final state Chiral many body, intial states oriented molecules Theoretical Prediction: Dubs, McCoy PRL 45 (1985) Pioneering Experiment: Circular Dichroism CO on surface Schönhense et al

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22 1.3 eV 10 eV 25 eV Multiple Scattering Theory: R. Diez Muino, M.van Hove, D. Rolles, C. Fadley, F. Garcia de Abajo

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24 Circular Dichroism from Aligned Molecules? 9 eV K-Shell N 2 Circular light measures PHASE SHIFTS (parallel/perp) Jahnke et al, PRL 88(2002)073002

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27 Zwischen Atomen und Molekülen: van der Vaals Cluster

28 Inter Atomic Coulombic Decay 1. Wie können Atome innere Energie abgeben? 2.Beeinflußt die Umgebung die Eigenschaften des Atoms?

29 Flourescence decay Decay processes of electronically excited particles: Auger decay Pierre Auger 1925 Energy 1s1s 2s2p Energy 1s1s 2s2p

30 Flourescence decay Decay processes of electronically excited particles: Auger decay Inter Atomic Coulombic Decay (ICD) (L. Cederbaum et al. PRL 79,4778(1997) energy transfer virtual photon exchange ICD electron from neighbor atom

31 Where? van der Vaals Cluster Hydrogen bonded systems Liquids

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33 Neon - Dimer 3.1 A Binding energy Ne meV van der Vaals Force

34 Neon - Dimer 3.1 A 1s 2s 2p Ne + Auger decay energetically forbidden from Ne + (2s -1 ) - 11eV 1s 2s 2p Ne energy transfer virtual photon exchange

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36 Ne +

37 single photon below Ne 2+ threshold Till Jahnke, et al. PRL 93, (2004)

38 Ne + Ne + Ne + Kinetic Energy Release (eV) electron energy (eV) 2s Photoelectron 5eV Energy of Ne 2 (2s -1 ) ICD electron

39 Ne + Santra et al. PRL 85, (2000) Ne 2 Ne 2 (2s -1 ) + Photo- electron 10eV h =59 eV Ne + ICD e - KER

40 Ne + Ne + Kinetic Energy Release (eV) electron energy (eV) Ne 2 Ne 2 (2s -1 ) + Photo- electron 10eV h =59 eV Ne + ICD e - KER

41 Ne + Ne + Kinetic Energy Release (eV) electron energy (eV) ICD-e - KER Photo-e - Ne 2 + (2s -1 ) Ne + ICD Santra et al PRL 85,4490(2000)

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43 1899 J.J. Thomson 1900 Elster & Gütel 1900 Lenard e-e- e-e- e-e- e-e- - A I low intensity high intensity Potential max. electron energy independent of intensity monochromatic light

44 24.6 eV eV 79 eV 0 Energy BIG Photon E >E bind

45 24.6 eV eV 79 eV 0 Energy Small Photon 1.5eV (800nm)

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47 24.6 eV eV 79 eV 0 Energy 53 nm W/cm 2

48 Extrem nichtlineare Prozesse von Störungstheorie (Elektronische)Materie unter extremen Bedingungen Extrem kurz Zeiten Attosekunden Elektronenbewegung sichbar machen Viele interessante Fragen:

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50 100um Ziel: W/cm 2 ????? Laser: 1 W, 800nm Faktor 10 6 Räumliche Kompression: 5 cm Brenweite: 5mm -> 5 um focus Zeitliche Kompression: 1kHz, 220 fsec ( ) Faktor um 5um

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52 Photo: S.Voss Lichtgeschosse: 3*3*3 m femto Sekunden Lichtgeschwindigkeit Leistungsdichte W/cm milli Joule GeV 2*10 15 Photonen (a 1.5 eV) Elektrische Felder > V/m

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54 Atom: Helium Photons Peak Power <10 16 W/cm 2 Standard Strong Field Laser (Ti Sa): fsec Field (10 16 W/cm 2 ) V/m 2.5 fsec (800nm) 0.15 fsec Field V/m


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