at ELI Beamlines Probing and Driving BioMolecular Dynamics with Femtosecond Pulses wavelengths 200 1200 nm energies below 1 mJ Why femtosecond lasers in chemistry and biology ID: 1044920
Download Presentation The PPT/PDF document "Miroslav Kloz Femtosecond spectroscopy" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
1.
2. Miroslav KlozFemtosecond spectroscopyat ELI BeamlinesProbing and Driving (Bio)Molecular Dynamics with Femtosecond Pulses (wavelengths 200 – 1200 nm, energies below 1 mJ)
3. Why femtosecond lasers in chemistry and biology?
4. Light matter interaction reflects its quantum structure ΔE = ħν
5.
6. asfspsnsScales of size and time are closely rerated!μsms
7. X-ray, electron (or other particles) experiments are practically rarely at natural conditionsTime resolution is just emergingExpensive, cannot be done at high throughputStructure does not directly explain function
8. Optical spectroscopy can explore matter at multiple levels in relatively non-invasive ways in a relatively cost effective manner.
9. Pump probe experiments
10. BLUF domainBiological photo sensorUsing FAD(Flavin Adenine Dinucleotide)as cofactor(biological APD…)
11. Flavin,Cofactor operating in visibleVisible near UVfs-ns
12. Amino acidsUVfs-ns
13. Bond structure (vibration spectroscopy)Mid IRfs-μs
14. Direct: (Ephoton = Etransition) (Mid Infrared)Raman: ΔE = EtransitionΔEΔEE
15. Backbone bulk modesTHzps - ms
16. Parametric amplification allows converting pulses into other wavelengths
17. Typical tuning curves
18. High power VIS + near UV/IRVIS + UV + IRMID - IRUltrashortshapedspectrally narrowed
19. Time window
20. 1 fs = 0.000 000 000 000 001 s~0.1 sfastest process we can perceive by our senses~2.5 x 109 s ~ Life of average men~4.3 x 1017 s since “Big Bang”FemtosecondCommon life experienceToo slowToo fast
21. 1 kHz Regenerative amplifier 11 fs < Δt < 1 msgate1 kHz Regenerative amplifier 282 MHz oscillator seedModern femtosecond laser technology allows to scan 10 orders of magnitude of dynamic range in a single experiment
22.
23. 2D spectrocopy
24. Too many combinations….At certain size incomputable…
25. Bump keyLock pickingTime domain 2DFrequency domain 2D
26. Link to 3D structure is much more direct!excite one vibration…Mapping GFP structure evolution during proton transfer with femtosecond Raman spectroscopyNature (12 November 2009)Fang,...Mathies…and observe effect on the other
27.
28. TOCSY spectra of a peptideNMRPhoton echo of Fenna-Matthews-Olson complex(Nature, 2007)
29. fs-mid-IRps-Vis“Conventional” 2D IRMixed2D IR x Ramanultrashort ~5fs visRaman in time domain2D visibleWhole series of 2D spectroscopies can be run In some cases even simultaneously.X-ray Raman resonant with core electrons
30. Pulse shaping
31. Femtosecond pulse is stabilized superposition of continuous weaves
32. Pulse shaping is like tuning to the exact melody to which the system responses
33. Behavior of the molecule can be selectively affected
34.
35. Tvarovač pulzů
36. Typical femtosecond set up
37.
38.