Structural dynamics study of small molecules using time-resolved X-ray solution scattering and time-resolved X-ray absorption spectroscopy = 용액상 시간분해 X-선 회절 및 시간분해 X-선 흡수 분광법을 이용한 작은 분자들의 구조 동역학 연구

Cited 0 time in webofscience Cited 0 time in scopus
  • Hit : 373
  • Download : 0
Knowing exact molecular structure is essential for understanding the properties of molecules, their interaction with the environment and the reaction mechanism. Many structural methods such as X-ray crystallography, electron diffraction, solution scattering, NMR, and XAFS have been developed and greatly improved, but identifying exact molecular structure in solution is still not a trivial job. Recently, we developed pump-probe X-ray solution scattering by using the X-ray pulse, instead of optical pulse, as a probe and gives the time-resolved scattering response sensitive to global molecular structure. Pump-probe X-ray solution scattering is a tool to circumvent limitations of optical spectroscopy and other structural methods. Since X-ray scatter from all atoms in the solution sample, TRXS can track not only the reaction pathways of the solute molecules but also the solvent behavior and the solute-solvent arrangement, thus providing a global picture of the reactions. We has had much success in visualizing structural dynamics of small molecules and proteins in solution with 100 ps time resolution using pump-probe X-ray solution scattering technique based on 3rd-generation synchrotrons. For example, TRXS has found that the major reaction intermediates upon photodissociation in iodoform (CHI3) is CHI2 radical rather than CHI2-I isomer and it is contradict to the previous spectroscopic studies. We have also used TRXS to identify famous symmetry breaking phenomena occurred in the I3- ion in water solution. I3- ion has asymmetric-bent structure in water solution while it has symmetric linear structure in acetonitile solution. With the aid of X-ray free electron lasers, the time resolution of TRXS can be improved to 100 fs. With this higher resolution, real time observation of ultrafast chemical events such as bond-breaking and bond-making will be possible.
Advisors
Ihee, Hyot-Cherlresearcher이효철
Description
한국과학기술원 : 화학과,
Publisher
한국과학기술원
Issue Date
2013
Identifier
514002/325007  / 020087107
Language
eng
Description

학위논문(박사) - 한국과학기술원 : 화학과, 2013.2, [ iii, 94 p. ]

Keywords

structural dynamics; solution scattering; X-ray absorption spectroscopy; 구조동역학; 용액상 회절; X-선 흡수분광법; X-선 회절법; X-ray scattering

URI
http://hdl.handle.net/10203/180281
Link
http://library.kaist.ac.kr/search/detail/view.do?bibCtrlNo=514002&flag=dissertation
Appears in Collection
CH-Theses_Ph.D.(박사논문)
Files in This Item
There are no files associated with this item.

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0