Written in English
|LC Classifications||Microfilm 94/2894 (Q)|
|The Physical Object|
|Pagination||viii, 133 leaves|
|Number of Pages||133|
|LC Control Number||94628293|
The ultrafast torsional isomerization and ring closure reactions of photoexcited cis-stilbene have been examined in hexane, cyclohexane, Reaction Dynamics in Clusters and Condensed Phases. Download book Cited by: 1. Dynamics Simulations with Spin-Flip Time-Dependent Density Functional Theory: Photoisomerization and Photocyclization Mechanisms of cis-Stilbene in ππ* States. The Journal of Physical Chemistry A , (51), Cited by: Isomerization of cis-stilbene in rare-gas clusters: direct measurements of trans-stilbene formation rates on a picosecond time scale. Journal of the Optical Society of America B , 7 (8), Molecular dynamics simulation with an ab initio potential energy function and finite element interpolation: The photoisomerization of cis -stilbene in solution. The Journal of Chemical Physics , (21), DOI: /
We have used a simple At + synchronously pumped and cavity-dumped dye-laser system to generate UV picosecond pulses with energies sufficiently high for absorption recovery experiments. With these pulses, we have studied the dynamics of the isomerization of trans-stilbene in n-alcohols as a function of viscosity and is concluded that the excited-state barrier of trans-stilbene in. Schematic diagram of nuclear wavepacket dynamics for cis-stilbene in solution. Q, ∼ cm −1 vibrational coordinate; ϕ, the isomerization coordinate. In the course of preparation of this manuscript, femtosecond time-resolved photoionization study of S 1 cis -stilbene in the gas phase was reported by Fuß et al. . The fluorescence decay time of cis‐stilbene has been measured in a variety of solvents over a large temperature range. An isoviscosity Arrhenius plot in n‐alkanes yields an activation energy of ±29 cm−1. We interpret this result as an upper limit for the cis‐stilbene to trans‐stilbene barrier in nonpolar solvents. Isoviscosity plots in small alcohols are nonlinear, indicating. The absence of efficient 4 -~ 4 isomerization, following triplet sensitization of ne , despite - - the cm energy excess, shows that there is at least one maximum in the T1 potential. Saltiel [63 pro- posed empirically that both the S1 and T1 potentials have minima at t, p and a with intermediate maxima.
The results confirm that both trans and cis fluorescence originating from excitation of pure cis-stilbene solutions are due to single photon excitation of 1 c to 1 c*. The quantum yield for adiabatic 1 c*→ 1 t* conversion is φ ct *=, independent of excitation wavelength. The photochemistry of cis-stilbene proceeds through two pathways: cis-trans isomerization and ring closure to 4a,4b-dihydrophenanthrene (DHP). Despite serving for many decades as a model system for photoisomerization, the photodynamics of cis-stilbene is still not fully understood. We use ab initio multiple spawning on a SACASSCF(2,2) potential energy surface to simulate the nonadiabatic. The fluorescence decay time of cis‐stilbene has been measured in a variety of solvents over a large temperature range. An isoviscosity Arrhenius plot in n‐alkanes yields an activation energy of ±29 cm − interpret this result as an upper limit for the cis‐stilbene to trans‐stilbene barrier in nonpolar solvents. Isoviscosity plots in small alcohols are nonlinear, indicating. The photoisomerization of cis-stilbene in liquid solution was studied by time-resolved excited-state absorption spectroscopy using nm pump and nm probe pulses of fs width.