title: Determination of the formation of dark state via depleted spontaneous emission in a complex solvated molecule.
abstract: We present a general two-color two-pulse femtosecond pump-dump approach to study the specific population transfer along the reaction coordinate through the higher vibrational energy levels of excited states of a complex solvated molecule via the depleted spontaneous emission. The time-dependent fluorescence depletion provides the correlated dynamical information between the monitored fluorescence state and the SEP "dumped" dark states, and therefore allow us to obtain the dynamics of the formation of the dark states corresponding to the ultrafast photoisomerization processes. The excited-state dynamics of LDS 751 have been investigated as a function of solvent viscosity and solvent polarity, where a cooperative two-step isomerization process is clearly identified within LDS 751 upon excitation.
authors.affiliation: The State Key Laboratory of Molecular Reaction Dynamics, and Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China.
authors.forename: Xunmin
authors.initials: X
authors.lastname: Guo
authors.forename: Sufan
authors.initials: S
authors.lastname: Wang
authors.forename: Andong
authors.initials: A
authors.lastname: Xia
authors.forename: Hongmei
authors.initials: H
authors.lastname: Su
mesh_terms: D015394:Molecular Structure; D009930:Organic Chemicals / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*; D013053:Spectrophotometry; D013997:Time Factors
chemical_list: D009930:Organic Chemicals; D012997:Solvents; C057718:6-(Dimethylamino)-2-((1E,3E)-4-(4-(dimethylamino)phenyl)-1,3-butadien-1-yl)-1-ethylquinolinium perchlorate