Symmetry properties of electronically excited states of nitroaromatic compounds

Autor:	Wei Kong, Xianzhao Peng, James E. Abbott
Rok vydání:	2002
Předmět:	Bond dipole moment Chemistry Transition dipole moment General Physics and Astronomy Photochemistry Polarization (waves) Molecular physics Dipole Electric field Excited state Physics::Atomic Physics Physical and Theoretical Chemistry Electric dipole transition Excitation
Zdroj:	The Journal of Chemical Physics. 117:8670-8675
ISSN:	1089-7690 0021-9606
DOI:	10.1063/1.1513992
Popis:	We report polarization spectroscopy of oriented gas phase nitroaromatic compounds, specifically nitrobenzene and the three isomers of nitrotoluene. Orientation of supersonically cooled molecules was achieved in a uniform electric field. The dependence of the yield of NO on the polarization direction of the excitation laser was used to derive the direction of the transition dipole. The transition to the S2 state centered at 250 nm demonstrated increased yield when the excitation laser was polarized perpendicular to the orientation field. The transition dipole was therefore characterized to be near perpendicular to the permanent dipole. The transition to S3 showed an opposite behavior, indicating that the transition dipole for S3 is primarily parallel to the permanent dipole. Quantitative analysis of the polarization dependence further revealed that in both cases, the transition dipole is not strictly parallel or perpendicular to the permanent dipole, and the tilt is about 20°–30°. This result demonstrates ...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::0b628296958dba0c9b0fc542e90ce8e9 https://doi.org/10.1063/1.1513992 Zobrazit plný text záznamu