1. Observation of Coherent molecular oscillation : Herzberg-Teller type Wave Packet Motion in Porphyrin J-aggregates MIYASAKA Lab. Tetsuro KATAYAMA

2. Contents “Observation of Herzberg － Teller-type Wave Packet Motion in Porphyrin J-Aggregates Studied by Sub-5-fs Spectroscopy” H. Kano, T. Saito,and T. Kobayashi. J. Phys. Chem. A, 2002, 106, 3445 Coherent molecular oscillation Franck-Condon type Wave Packet Motion Herzberg-Teller type Wave Packet Motion

3. Introduction N. F. Scherer, et al., JCP,1993, 99, 153 Coherent molecular oscillation observed by femtosecond transient spectroscopy Coherent molecular oscillation ： コヒーレントな分子振動 Iodine ： ヨウ素 (I 2 )

4. Coherent molecular oscillation Probe Pump Detector Delay Time Sample 0 0 t t A ⊿ A ⊿ τ ･ Photoinduced absorption ･ Photo-bleaching, stimulated emission Pump-probe spectroscopy Photoinduced (Transient) absorption ： 過渡吸収 Stimulated emission ： 誘導放 出 Photo-bleaching ： ブリーチ

5. Franck-Condon type wave packet motion Linear coupling assuming harmonic oscillator Energy Nucleus separation ･ The curvature is the same. ･ Equilibrium nuclear position is different. ･ Coherent oscillation of transient absorption and stimulated emission are observed ･ Raman transitions causes wave packet motion in the ground state which can be observed in the photo-bleaching excited state ground state Franck-Condon type wave packet motion ： フランクコンドン型波束運動 Raman transitions ： ラマン遷移 Equilibrium nuclear position ： 平衡核間距離 oscillate

6. Overtone was observed at 526nm probe for iodine 580 nm pump 580 nm probe 580 nm pump 526 nm probe 211 cm -1 420 cm -1 Overtone ： 倍音 N. F. Scherer, et al., JCP,1993, 99, 153

7. Why was overtone observed ? Typical Franck-Condon type wave packet motion 524 nm Center Turning point 580 nm,480 nm I 2 excited state energy surfaces ground state N. F. Scherer, et al., JCP,1993, 99, 153

8. Theory Herzberg-Teller type wave packet motion Energy Nucleus separation ･ The curvature is the same. ･ No displacement between the equilibrium position. ･ Transition frequency do not depend on the wave packet position. ･ In Herzberg-Teller type model. Transition dipole moment depends on the wave packet position μ+δμ μ μ-δμ Herzberg-Teller type wave packet motion ： ヘルツベルグテラー型波束運動 constant

9. Two types of wave packet motion Wavelength ⊿ Franck-Condon type Herzberg-Teller type A

10. Experimental Sample Tetraphenylporphine tetrasulfonic acid ( TPPS 4 ) ～ 2nm J-aggregate R. Rotomskis et al J. Phys. Chem.B, 2004, 108, 2833 J-aggregate ： Ｊ会合体

11. AFM image of Macroscopic TPPS 4 J-aggregates AFM ： 原子間力顕微鏡法 (AFM image) (Optical microscopy) Optical microscopy ： 光学顕微鏡 R. Rotomskis et al J. Phys. Chem.B, 2004, 108, 2833

12. Stationary absorption and fluorescence H.Kano.et at.Journal of the Chinese Chemical Society, 2000, 47, 859 Stokes shift is very small (>20meV)

13. Transient absorption spectrum Photo-bleaching and stimulated emission Transient absorption 320fs

14. Probe wavelength dependence of the coherent oscillation Overtone wasn’t observed Amplitude Reversed at ～ 1.78eV

15. Resonance Raman spectrum ruffling mode It is attributed to out-of-plane ruffling mode

16. Frequency dependence of the initial phase and amplitude Initial phase is constant Amplitude is reversed around 1.78eV(697nm) It might not be Franck-Condon type

17. Oscillation was observed in the integrated signal Oscillation was also observed in the integrated signal from 1.65 to 1.91eV(752nm to 649nm) It might not be Franck-Condon type 247cm -1

18. Justification of Herzberg-Teller type 1 Stokes shift was small(>20meV) 2 Over tone wasn’t observed at any wavelength 3 Amplitude was reversed around 1.78eV but phase was constant. 4 Coherent oscillation was also observed from integrated signal

19. Summary The wave packet observed in the present study can be classified as a Herzberg-Teller type in contrast with the frequently studied conventional Franck-Condon type.

20. vibration : Window function

21. X-ray Crystallography Ⅰ

22. X-ray Crystallography Ⅱ

23. How know formation of j-aggregate? J-band

24. Dynamic IntensityBorrowing -Vibronic coupling -Configration interaction

25. Vibronic coupling parity-forbidden a vibration of the molecule can destroy the Inversion symmetry The removal of the centre of symmetry gives rise to a vibronically allowed transition.

27. Experimental Setup Laser system

28. Introduction Pump-Probe Spectroscopy Probe Pump Transmittance Detection Delay Time Sample

29. ･ What is Window function ?

30. J-aggregate

31. Why is Stokes shift small ? Frenkel exiciton : TPPS : Transition dipole moment

32. Frenkel exiciton make a mode strong Atkins,D.L. et al,J. Phys. Chem., 1996, 100, 14391

33. Problem Really was it observed ? E.A.Carson,et al.,J.phys.Chem.A 2004,108,1489-1500

34. Theory Herzberg-Teller type μ μ+δμ － δμ +δμ μ μ

36. Why does a wave packet form?

37. Results ＆ Discussions Stationary absorption T. Ogawa et al..Chemical Physics Letters,2005,408,186 J-band (J-aggregate) (Monomer) The laser spectrum

38. Resonance Raman spectrum