scholarly journals Insights into the excited state dynamics of Fe(ii) polypyridyl complexes from variable-temperature ultrafast spectroscopy

2019 ◽  
Vol 10 (1) ◽  
pp. 134-144 ◽  
Author(s):  
Monica C. Carey ◽  
Sara L. Adelman ◽  
James K. McCusker
Keyword(s):  
Excited State ◽  
Transition Metal ◽  
Ground State ◽  
Ultrafast Spectroscopy ◽  
Variable Temperature ◽  
Activation Parameters ◽  
Polypyridyl Complexes ◽  
Time Resolved ◽  
Excited State Dynamics ◽  
State Recovery

In order to better define the nature of the nuclear coordinate associated with excited state dynamics in first-row transition metal chromophores, variable-temperature ultrafast time-resolved absorption spectroscopy has been used to determine activation parameters associated with ground state recovery in a series of low-spin Fe(ii) polypyridyl complexes.

scholarly journals Outer-sphere effects on ligand-field excited-state dynamics: solvent dependence of high-spin to low-spin conversion in [Fe(bpy)3]2+

2020 ◽  
Vol 11 (20) ◽  
pp. 5191-5204 ◽  
Author(s):  
Jennifer N. Miller ◽  
James K. McCusker
Keyword(s):  
Excited State ◽  
Reorganization Energy ◽  
Outer Sphere ◽  
Ligand Field ◽  
Spin Conversion ◽  
Energy Effect ◽  
Time Resolved ◽  
Excited State Dynamics ◽  
State Recovery ◽  
Solvent Dependence

Time-resolved spectroscopic measurements of ground-state recovery for [Fe(bpy)3]2+ reveal that the solvent can induce an outer-sphere reorganization energy effect on excited-state dynamics involving metal-centered ligand-field electronic states.

scholarly journals The influence of the FeCp(CO)2+moiety on the dynamics of the metalloid [Ge9(Si(SiMe3)3)3]−cluster in thf: synthesis and characterization by time-resolved absorption spectroscopy

2019 ◽  
Vol 48 (41) ◽  
pp. 15577-15582 ◽  
Author(s):  
Nadine C. Michenfelder ◽  
Christian Gienger ◽  
Andreas Schnepf ◽  
Andreas-Neil Unterreiner
Keyword(s):  
Transition Metal ◽  
Absorption Spectroscopy ◽  
Ground State ◽  
Strong Influence ◽  
Synthesis And Characterization ◽  
Time Resolved ◽  
State Recovery ◽  
Covalently Bound

Photoexcitation of a newly synthesized, neutral tetrasubstituted Ge9cluster with a covalently bound transition metal substituent led to a complete ground state recovery within 150 ps indicating the strong influence of the Fe moiety.

Excited state dynamics and time-resolved photoelectron spectroscopy of para-xylylene

2018 ◽  
Vol 212 ◽  
pp. 83-100 ◽  
Author(s):  
Kevin Issler ◽  
Anja Röder ◽  
Florian Hirsch ◽  
Lionel Poisson ◽  
Ingo Fischer ◽  
...  
Keyword(s):  
Excited State ◽  
Ground State ◽  
Photoelectron Spectroscopy ◽  
Time Scale ◽  
Time Resolved ◽  
Surface Hopping ◽  
Excited State Dynamics ◽  
Ultraviolet Excitation ◽  
Step Mechanism

We investigated the excited-state dynamics of para-xylylene using a combination of field-induced surface hopping simulations and time-resolved photoionisation experiments. Ultraviolet excitation is followed by nonadiabatic relaxation to the ground state in a two-step mechanism on the sub-ps time scale.

scholarly journals Signatures of Conical Intersection Dynamics in the Time-Resolved Photoelectron Spectrum of Furan: Theoretical Modeling with an Ensemble Density Functional Theory Method

2021 ◽  
Vol 22 (8) ◽  
pp. 4276
Author(s):  
Michael Filatov ◽  
Seunghoon Lee ◽  
Hiroya Nakata ◽  
Cheol-Ho Choi
Keyword(s):  
Excited State ◽  
Ground State ◽  
Density Functional ◽  
Binding Energies ◽  
Photoelectron Spectra ◽  
Time Resolved ◽  
Excited State Dynamics ◽  
Wide Range ◽  
Electron Binding Energies ◽  
Electron Binding

The non-adiabatic dynamics of furan excited in the ππ* state (S2 in the Franck–Condon geometry) was studied using non-adiabatic molecular dynamics simulations in connection with an ensemble density functional method. The time-resolved photoelectron spectra were theoretically simulated in a wide range of electron binding energies that covered the valence as well as the core electrons. The dynamics of the decay (rise) of the photoelectron signal were compared with the excited-state population dynamics. It was observed that the photoelectron signal decay parameters at certain electron binding energies displayed a good correlation with the events occurring during the excited-state dynamics. Thus, the time profile of the photoelectron intensity of the K-shell electrons of oxygen (decay constant of 34 ± 3 fs) showed a reasonable correlation with the time of passage through conical intersections with the ground state (47 ± 2 fs). The ground-state recovery constant of the photoelectron signal (121 ± 30 fs) was in good agreement with the theoretically obtained excited-state lifetime (93 ± 9 fs), as well as with the experimentally estimated recovery time constant (ca. 110 fs). Hence, it is proposed to complement the traditional TRPES observations with the trXPS (or trNEXAFS) measurements to obtain more reliable estimates of the most mechanistically important events during the excited-state dynamics.

Excited-State Dynamics in the RNA Nucleotide Uridine 5’-Monophosphate Investigated by Femtosecond Broadband Transient Absorption Spectroscopy

2019 ◽  
Author(s):  
Matthew M. Brister ◽  
Carlos Crespo-Hernández
Keyword(s):  
Excited State ◽  
Excited States ◽  
Ground State ◽  
Transient Absorption ◽  
Electronic Energy ◽  
Transient Absorption Spectroscopy ◽  
Electronic Relaxation ◽  
Vibrationally Excited ◽  
Excited State Dynamics ◽  
Π State

<p></p><p> Damage to RNA from ultraviolet radiation induce chemical modifications to the nucleobases. Unraveling the excited states involved in these reactions is essential, but investigations aimed at understanding the electronic-energy relaxation pathways of the RNA nucleotide uridine 5’-monophosphate (UMP) have not received enough attention. In this Letter, the excited-state dynamics of UMP is investigated in aqueous solution. Excitation at 267 nm results in a trifurcation event that leads to the simultaneous population of the vibrationally-excited ground state, a longlived <sup>1</sup>n<sub>O</sub>π* state, and a receiver triplet state within 200 fs. The receiver state internally convert to the long-lived <sup>3</sup>ππ* state in an ultrafast time scale. The results elucidate the electronic relaxation pathways and clarify earlier transient absorption experiments performed for uracil derivatives in solution. This mechanistic information is important because long-lived nπ* and ππ* excited states of both singlet and triplet multiplicities are thought to lead to the formation of harmful photoproducts.</p><p></p>

Excited-state dynamics of guanosine in aqueous solution revealed by time-resolved photoelectron spectroscopy: experiment and theory

2015 ◽  
Vol 17 (47) ◽  
pp. 31978-31987 ◽  
Author(s):  
Franziska Buchner ◽  
Berit Heggen ◽  
Hans-Hermann Ritze ◽  
Walter Thiel ◽  
Andrea Lübcke
Keyword(s):  
Aqueous Solution ◽  
Excited State ◽  
Photoelectron Spectroscopy ◽  
Relaxation Dynamics ◽  
Time Resolved ◽  
Excited State Dynamics ◽  
Spectroscopy Experiment

Time-resolved photoelectron spectroscopy is performed on aqueous guanosine solution to study its excited-state relaxation dynamics.

Sign in / Sign up

Export Citation Format

Share Document