Stereodirectional images of molecules oriented by a variable-voltage hexapolar field: Fragmentation channels of 2-bromobutane electronically excited at two photolysis wavelengths
| Autor: | Federico Palazzetti, Vincenzo Aquilanti, Shiun-Jr. Yang, Dock-Chil Che, Andrea Lombardi, Masaaki Nakamura, Toshio Kasai, King-Chuen Lin |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
education.field_of_study
010304 chemical physics Linear polarization Population General Physics and Astronomy 010402 general chemistry Polarization (waves) 01 natural sciences 0104 chemical sciences Ion chemistry.chemical_compound Wavelength chemistry Excited state 0103 physical sciences Physical and Theoretical Chemistry Atomic physics education 2-Bromobutane Molecular beam |
| Popis: | The asymmetric-top molecule 2-bromobutane is oriented by means of a hexapole state selector; the angular distribution of the bromine atom photofragment, for the two fine-structure components, is acquired by velocity-map ion imaging. The molecular beam, spatially oriented along the time-of-flight axis, is intersected with a linearly polarized laser, whose polarization is tilted by 45° with respect to the detector surface. To obtain the mixing ratio of the perpendicular and parallel transitions, the fragment ion images and angular distributions can be appropriately simulated to give insight on the population mechanism of the specific electronic state involved at each selected excitation wavelength. The photofragment images obtained at 238.6 nm yielded an asymmetry factor β1 of 0.67, indicative of the extent of molecular orientation, and an anisotropy parameter β2 of 1.03, which is a signature of a prevailing parallel transition along the C–Br axis. When the photolysis wavelength is tuned to 254.1 nm, the co... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|