Raman spectroscopy: Variants and potentials

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1 Carl-Zeiss lecture Jena Raman spectroscopy: Variants and potentials Hiro-o Hamaguchi National Chiao Tung University, Taiwan The University of Tokyo, Japan Wseda University, Japan

2 Raman spectroscopy: Variants and potentials Y / µm Raman brothers, Raman, CARS/SRS, and SERS/TERS What do they look at? Hamaguchi s score sheet for Raman brothers Raman spectroscopy in Japan Discovery of rotational isomerism Normal coordinate analysis Time-resolved Raman spectroscopy Dynamic polarization model of chemical reactions 16 Raman microsepctroscopy of living cells Tailor-made Raman spectroscopy

3 Raman Spectroscopy Anti-Stokes Raman Rayleigh Stokes Raman Raman scattering: Inelastic light scattering discovered by C. V. Raman in 1928 Raman spectroscopy: Spectroscopy utilizing Raman scattering C. V. Raman ( )

4 Raman Brothers: What do they look at? Raman SERS/ TERS CARS

5 Normal Mode of Vibration: The Totally Symmetric C-C Stretch Mode of an Acetone Molecule

6 Vibrational Motions of Ensembles of Acetone Molecules

7 p = ae What Does Raman look at?

8 Raman Looks at a Normal Mode of Vibration.

9 Raman Gives a Molecular Fingerprint.

10 What Does CARS/SRS Look at?

11 CARS/SRS Looks at a Vibrational Coherence p = ce 12 E 2

12 CARS Can Give a Molecular Fingerprint After Some Mathematical Treatments. CARS spectra Imc 3 spectra by MEM Imc 3 spectra after SVD Raman spectra Okuno et al. Angewandte Chemie, Angew. Chem. Int. Ed., 49, (2010).

13 Vibrational Motions of Ensembles of Acetone Molecules

14 What Does SERS/TERS Look at?

15 SERS/TERS is Likely to Look at a Local Molecular Motion (May not be a Normal Mode)

16 SERS/TERS May not Give a Full Molecular Fingerprint.

17 Hamaguchi s Score Sheet for Ramans Selection rule Polarization rule Information content Raman CARS/SRS SERS/TERS Established Established Molecular Fingerprint Established for homogeneous systems Established for homogeneous systems High polarization capabilities Molecular fingerprint after mathematics Dependence on individual molecular orientation? Dependence on individual molecular orientation? Molecular Fingerprint? Sensitivity Ensemble Ensemble Single molecule Spatial resolution 0.61l/NA (500 nm) 0.61l/NA 3 (300 nm) Tip size (10 nm) Time resolution ps ps ps Experimental difficulty Fluorescence interference Phase match/mismatch Tip/substrate dependence

18 Raman is HH s first choice for advanced applications. CARS/SRS surpasses Raman for its polarization capabilities. SERS/TERS excels in sensitivity and spatial resolution. Its information content yet to be clarified.

19 Raman Spectroscopy attokyo

20 Discovery of the Rotational Isomerism Trans Gauche Gas Liquid Crystal S. Mizushima ( )

21 Raman Spectra are letters from the molecule Vibrational Raman spectra are molecular fingerprints Professor Takehiko Shimanouchi ( )

22 T. Shimanouchi, Tables of Molecular Vibrational Frequencies, NSRDS-NBS 39.

23 High Resolution Raman Spectrometer (1972)

24 Raman Gas Cell in Laser Cavity (1972)

25 Raman Spectrum of CH 3 I (1972)

26 Resonance Raman scattering

27 Theory of Resonance Raman Scattering Albrecht s vibronic theory of resonance Raman Scattering A. C. Albrecht, J. Chem. Phys. 34, 1476 (1961). a rs ~ A + B A. C. Albrecht ( ) A term: Franck-Condon term Totally symmetric modes High overtones B term: Vibronic coupling Non-totally symmetric modes No high overtones

28 Raman Active Vibrations of MX 6 Octahedral Complexes n 1 (a 1g ) n 2 (e g ) n 5 (t 2g ) a 1g ~ e g ~ t 2g ~ r=0 r=0.75 r=0.75

29 Resonance Raman spectrum of PtI 6 2- PtI nm excitation Totally symmetric mode (n 1, 2n 1, 3n 1 ) A term Non-totally symmetric mode ( n 2, 2n 2, n 1 +n 2, 2n 1 +n 2 ) B term H. Hamaguchi, I. Harada, T. Shimanouch, J. Raman Spectrosc., 2, (1974).

30 Polarized Resonance Raman Spectra of PtI 6 2- PtI nm excitation n 1, 2n 1, 3n 1 bands r=0 ; n 2 band r=0.75 H. Hamaguchi, J. Chem. Phys., 69, (1978).

31 Polarized Resonance Raman Spectra of IrBr 6 2- IrBr nm excitation r=1 for all bands; forgot to rotate the analyzer? H. Hamaguchi, J. Chem. Phys., 66, (1977); 69, (1978).

32 Raman Scattering Tensors and Depolarization ratio of the Totally Symmetric Mode of the IrBr 6 2- Ion g(a)> g(a)> g(b)> g(b)> g(a)> g(b)> g(a)> g(b)> 1 i 0 -i i i i i i 0 i G 0 =3, G a =2, G s =0 G 0 =0, G a =4, G s =0 G 0 =0, G a =4, G s =0 G 0 =3, G a =2, G s =0 G 0 =6, G a =12, G s =0 r=(3g s +5G a )/(10G 0 +4G s )=1 H. Hamaguchi, J. Chem. Phys., 66, (1977).

33 (1985)

34 Nanosecond Transient Raman Spectrometer (1983)

35 Photoisomerization of Trans-Stilbene Why, when and how rotation occurs in the excited state? Solvent-dependent isomerization rate Hexane 70 ps Dodecane 120 ps hn Probe solvent dependent structure and dynamics of S 1 trans-stilbene by time-resolved Raman spectroscopy

36 Nanosecond Transient Raman Spectrum of S 1 Trans-Stilbene (1983) T. L. Gustafson, D. M. Roberts, and D. A. Chernoff, J. Chem. Phys. 79, 1559 (1983). H. Hamaguchi, C. Kato, M. Tasumi, Chem. Phys. Lett., 100, 3-7 (1983).

37 Three Raman Stilbenists on a Bridge near the Noishvanstein Castle (1985)

38 (1987)

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41 Koichi Iwata Volker Deckert

42 Picosecond Time-resolved Raman Spectrometer pulse compressor SHG sync. pumped dye laser 82 MHz 588 nm AO cw mode-locked Nd:YAG laser dye amplifier PD cw Nd:YAG regenerative amplifier polychromator multichannel detector (CCD) UV cut filter band-reject filter sample dichroic mirror SHG variable ND pump 294 nm 2.2 ps probe 588 nm 3.2 ps 3.5 cm-1 SHG optical delay dichroic mirror 588 nm 3.2 ps 3.5 cm nm 2.2 ps S n S 1 S 0 Trans-Stilbene

43 -2 ps -1 ps 0 ps 1 ps 2 ps 3 ps 5 ps 7 ps 10 ps 15 ps 20 ps 30 ps 40 ps 50 ps 70 ps 100 ps S 1 trans-stilbene in CHCl 3-10 ps Pump 294 nm Probe 588 nm (0.1 mw) Raman Shift / cm -1 C=C stretch vibration 1560 cm -1 : double bond Why rotation occurs around a double bond?

44 The C=C Stretch Raman Band of S 1 trans-stilbene in Alkanes Hexane Heptane Octane Nonane Decane Dodecane Hexadecane Raman Shift / cm -1 The peak position shifts to higher wavenumbers and the band width decreases on going from hexane to hexadecane. Why?

45 Peak Position vs Band Width in Alakne Solvents at Different Temperatures 1574 hexane octane decane Peak position / cm Why does linear Relation hold? Bandwidth / cm -1

46 Dynamic Frequency Exchange Model and Vibrational Bandshapes (a) Two Frequency Exchange Model Hamaguchi Mol. Phys.89, 463 (1997). W 1 (b) Many Frequency Exchange Model DW = W 1 t/(1+t 2 ) DG = W 1 t 2 /(1+t 2 ) DG / DW = t DW = W DG = W W 2 n 2 1 ( W1 / W1 ) t /(1 + t = 2 n ( W1 / W1 ) t /(1 + t = 2 ), ), (c) Continuous Frequency Modulation Model 0 2 W1 G( t ) t /(1 + t ) dt DW= 0 G( t ) dt W1 G( t ) t /(1 + t ) dt DG = 0 G( t ) dt DG / DW = t 1/2 ; G(t)=exp(-ln2t 2 /t 1/22 )

47 Peak Position vs Band Width in Alakne Solvents at Different Temperatures 1574 hexane octane decane Peak position / cm DW = W 1 t/(1+t 2 ) DG = W 1 t 2 /(1+t 2 ) DG / DW = t t = Bandwidth / cm -1

48 Fitting of the C=C Stretch Raman Band of S1 trans- Stilbene by the Two Frequency Exchange Model Fitting of the observed band shapes Hexane Obs Fit W 1 =2.7x10 12 sec -1 (370 (fs) -1 ) W 1 Dodecane W 2 W 1 =1.5x10 12 sec -1 (670 (fs) -1 ) Raman shift / cm -1

49 Isomerization Rate k iso is Proportional to W 1 0 DW =0 DW / cm K 293 K 298 K 303 K 313 K DW = W 1 t/(1+t 2 ) t =1.4 W1 / s -1 1x k iso / s x10 9

50 Dynamic Polarization Model of Isomerization W 1 W 2 Isomerization Hamaguchi, Iwata, CPL 208, 465 (1993). Deckert, Iwata, Hamaguchi, J. Photochem. Photobiol. 102, 35 (1996). Iwata, Ozawa, Hamaguchi, JCP 106, 3614 (2002).

51 How Do Chemical Reactions Proceed? A A* B A A* B Cf. Michaelis-Menten kinetics

52 How can the events in space and time which take place within the spatial boundary of a living organism be accounted for by physics and chemistry? In What is Life Erwin Schrödinger E. Schrödinger ( )

53 Raman Spectroscopy of Really Living Cell 0min 6min 11min 24min 31min 41min 53min 62min 69min 72min Wavenumber / cm -1 Y-S Huang, T. Karashima, M. Yamamoto, H. Hamaguchi, J. Raman Spectrosc., 34, 1-3 (2003).

54 Molecular Component Distribution Imaging (MCDI) of Living Cells with Multivariate Curve Resolution Analysis white blood cell Page 54 Thorough interpretation of complicated spectra is very difficult.

55 Singular value Multivariate Analysis Matrix factorization by Singular Value Decomposition (SVD) n A WSH n m m n

56 Singular value Multivariate Curve Resolution (MCR) k is determined n k n SVD m m Initial guess Page 56 Random or SVD based Alternating Least-Squares A WH 2 is minimized

57 Multivariate Analyses: Comparison SVD MCR W, H 0, L 1 = 0 MCR W, H 0, L 1 = 0.001

58 5 分類 White Blood Cells Neutrophil % μm Eosinophil 2-5 % μm Basophil < 1 % μm Lymphocyte % 7-8 μm Monocyte 3-6 % μm Phagocytosis - bacteria, fungi Combating parasites Modulate allergic inflammatory responses release histamine for inflammatory responses B cells T cells NK cells Differentiate into tissue resident macrophages Page 58

59 MCR Analysis of White Blood Cells Eosinophil Monocyte Neutrophil Lymphocyte Raman shift / cm -1 Page 59

60 MCDI of White Blood Cells Eosinophil Monocyte Neutrophil Lymphocyte nucleic acid protein Myeloperoxidase (MPO) Eosinophil peroxidase (EPO) protein background lipid (unsaturated) carotenoid Page 60

61 Organelle Specific Waters in a Living Cell (a) (b) (c) (d) (e) (e) S. Tiwari, M. Andoa and H. Hamaguchi, in preparation (a)

62 Broadband Multiplex CARS Microspectroscopy w 1 w 1 w 2 wcars n=1 w 1 pulse Dw 1 =20cm -1 n=0 w 2 pulse w 1 100~200pJ w 2 ~30pJ H. Kano and H. Hamaguchi, Anal. Chem., 79, (2007).

63 Vibrational CARS Movies of a Single Budding Yeast Cell w 1 : 10 mw, w 2 : 10 mw Expo. time/pixel: 30 msec Image acquisition time: ~ 12 sec

64 Multi-focus Confocal Raman Microspectroscopy M. Okuno and H. Hamaguchi, Opt. Lett., 35, (2010).

65 Y / µm Y / µm Y / µm Y / µm Budding yeast cells cm cm Laser power : 1 mw Exposure time: 1 sec Readout time: ~150 msec X / µm cm cm X / µm PZT scan 4 x 4 points 2 x 2 mm Total area: 16 x 12 mm X / µm X / µm Total image acquisition time (1 sec+ 0.2 sec) x 4 x 4 ~20 sec / image!!

66 Time/Space-resolved Raman Spectroscopy Space 10 cm 10 mm Time 10 9 s 10 3 s Organ Cell Biology 1 mm 10 2 s Organelle Liposome Ionic liquid Solvation structure Chemistry 10 nm s Aggregate Complex 1 nm s Molecule 0.1 nm s Atom Physics

67 Raman Measurement of Food in situ

68 Raman Application to Food Science Natural or cultured food resources Food processing Food safety & quality control: Food constituent Functional ingredient Contamination of pathogens or residual pesticides Label-free, less invasive and rapid analysis by using Raman spectroscopy

69 Intensity / a.u. Raman Spectra of Tuna Raman shift / cm -1 Page 69 Quantification of lipids / proteins evaluation of food quality and taste

70 Intensity ratio(lipid/protein) Intensity ratio(lipid/protein) Lipid Content Analysis of Tuna lean chutoro otoro 0 Tail (chutoro) Page 70

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72 First Student Summer Camp of Taiwan Association of Raman Spectroscopy ( at Jianshi)