Photodissociation, Recombination, and Electron Transfer in Cluster Ions:  A Nonadiabatic Molecular Dynamics Study of I2-(CO2)n

Delaney, N. D.; Faeder, James R.; Maslen, Paul E.; Parson, Robert

doi:10.1021/jp972435n

Cited by 40 publications

(81 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…1͒; however, both simulations 43,46 and experiment 11 show that in a cluster of CO 2 molecules this channel is closed and that dissociation only occurs via nonadiabatic transitions to the lower A and X states.…”

Section: Introductionmentioning

confidence: 94%

See 1 more Smart Citation

Simulation of UV photodissociation of I2−(CO2)n: Spin-orbit quenching via solvent mediated electron transfer

Delaney

Faeder

Parson

1999

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

We simulate the 395 nm photodissociation of I2− embedded in clusters of 6 to 22 CO2 molecules. In the isolated molecule, photodissociation at this wavelength leads exclusively to spin-orbit excited iodine (I*) plus I−. In the larger clusters we observe efficient electronic relaxation, leading both to dissociated products containing ground-state iodine and to recombined products containing I2−. The time scale and cluster size dependence of the spin-orbit quenching process agree well with experimental determinations of Sanov et al. (companion paper). The simulation trajectories show that spin-orbit quenching occurs by resonant charge transfer from solvated I− to a nascent I* atom. A model derived from the theory of electron transfer reactions in solution illustrates that this resonance arises when the I spin-orbit energy is compensated by the difference between the solvation energies of the ion and the neutral.

show abstract

Section: Introductionmentioning

confidence: 94%

“…[41][42][43][44][45][46] Nonadiabatic molecular dynamics simulations computed with these Hamiltonians have successfully reproduced the results of both time-independent and time-dependent experiments. The results of these simulations demonstrate that physical pictures based on the isolated molecule potential curves can be highly misleading.…”

Section: Introductionmentioning

confidence: 98%

Simulation of UV photodissociation of I2−(CO2)n: Spin-orbit quenching via solvent mediated electron transfer

Delaney

Faeder

Parson

1999

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…27-29 Delaney et al suggested that all four CO 2 molecules are in contact with I 2 − in I 2 − ͑CO 2 ͒ 4 : Three carbon dioxide molecules are around the waste of I 2 − and the fourth one is attached to one of the I atoms, causing asymmetric charge distribution along the I 2 axis. 28 If A − ͑O 2 ͒ 4 had a similar solvent arrangement as I 2 − ͑CO 2 ͒ 4 , it is not expected that all four O 2 molecules could be stripped off in less than one picosecond. Instead, we propose that O 2 molecules cluster together based on the tendency for quasi-O 4 -core formation in the presence of an extra electron, and this cluster sits on A − forming a single bond between A − and ͑O 2 ͒ n .…”

Section: B Vectorial Dynamicsmentioning

confidence: 99%

Ultrafast vectorial and scalar dynamics of ionic clusters: Azobenzene solvated by oxygen

Paik

Baskin

Kim

et al. 2006

The Journal of Chemical Physics

View full text Add to dashboard Cite

The ultrafast dynamics of clusters of trans-azobenzene anion ͑A − ͒ solvated by oxygen molecules was investigated using femtosecond time-resolved photoelectron spectroscopy. The time scale for stripping off all oxygen molecules from A − was determined by monitoring in real time the transient of the A − rise, following an 800 nm excitation of A − ͑O 2 ͒ n , where n =1-4. A careful analysis of the time-dependent photoelectron spectra strongly suggests that for n Ͼ 1 a quasi-O 4 core is formed and that the dissociation occurs by a bond cleavage between A − and conglomerated ͑O 2 ͒ n rather than a stepwise evaporation of O 2 . With time and energy resolutions, we were able to capture the photoelectron signatures of transient species which instantaneously rise ͑Ͻ100 fs͒ then decay. The transient species are assigned as charge-transfer complexes: A ·O 2 − for A − O 2 and A ·O 4 − · ͑O 2 ͒ n−2 for A − ͑O 2 ͒ n , where n =2-4. Subsequent to an ultrafast electron recombination, A − rises with two distinct time scales: a subpicosecond component reflecting a direct bond rupture of the A − -͑O 2 ͒ n nuclear coordinate and a slower component ͑1.6-36 ps, increasing with n͒ attributed to an indirect channel exhibiting a quasistatistical behavior. The photodetachment transients exhibit a change in the transition dipole direction as a function of time delay. Rotational dephasing occurs on a time scale of 2 -3 ps, with a change in the sign of the transient anisotropy between A − O 2 and the larger clusters. This behavior is a key indicator of an evolving cluster structure and is successfully modeled by calculations based on the structures and inertial motion of the parent clusters.

show abstract

“…[40] Molecular dynamics (MD) simulation adopting an effective Hamiltonian has been applied to understand photodissociation and recombination dynamics of I 2 C À ·n CO 2 clusters. [41] Solvated clusters of the solute I 2 C À with less interacting solvents like Ar have also been studied by experimental and theoretical techniques. Anion femtosecond photoelectron spectroscopy has been used to follow the dynamics of I 2 C À ·n Ar clusters subsequent to photodissociation of the I 2 C À chromophore.…”

Section: Introductionmentioning

confidence: 99%

Global Minimum‐Energy Structure and Spectroscopic Properties of I₂^.−⋅n H₂O Clusters: A Monte Carlo Simulated Annealing Study

2010

View full text Add to dashboard Cite

The vibrational (IR and Raman) and photoelectron spectral properties of hydrated iodine-dimer radical-anion clusters, I(2)(*-) x n H(2)O (n=1-10), are presented. Several initial guess structures are considered for each size of cluster to locate the global minimum-energy structure by applying a Monte Carlo simulated annealing procedure including spin-orbit interaction. In the Raman spectrum, hydration reduces the intensity of the I-I stretching band but enhances the intensity of the O-H stretching band of water. Raman spectra of more highly hydrated clusters appear to be simpler than the corresponding IR spectra. Vibrational bands due to simultaneous stretching vibrations of O-H bonds in a cyclic water network are observed for I(2)(*-) x n H(2)O clusters with n > or = 3. The vertical detachment energy (VDE) profile shows stepwise saturation that indicates closing of the geometrical shell in the hydrated clusters on addition of every four water molecules. The calculated VDE of finite-size small hydrated clusters is extrapolated to evaluate the bulk VDE value of I(2)(*-) in aqueous solution as 7.6 eV at the CCSD(T) level of theory. Structure and spectroscopic properties of these hydrated clusters are compared with those of hydrated clusters of Cl(2)(*-) and Br(2)(*-).

show abstract

Photodissociation, Recombination, and Electron Transfer in Cluster Ions: A Nonadiabatic Molecular Dynamics Study of I₂^-(CO₂)_n

Cited by 40 publications

References 26 publications

Simulation of UV photodissociation of I2−(CO2)n: Spin-orbit quenching via solvent mediated electron transfer

Simulation of UV photodissociation of I2−(CO2)n: Spin-orbit quenching via solvent mediated electron transfer

Ultrafast vectorial and scalar dynamics of ionic clusters: Azobenzene solvated by oxygen

Global Minimum‐Energy Structure and Spectroscopic Properties of I₂^.−⋅n H₂O Clusters: A Monte Carlo Simulated Annealing Study

Contact Info

Product

Resources

About

Photodissociation, Recombination, and Electron Transfer in Cluster Ions: A Nonadiabatic Molecular Dynamics Study of I2-(CO2)n

Cited by 40 publications

References 26 publications

Simulation of UV photodissociation of I2−(CO2)n: Spin-orbit quenching via solvent mediated electron transfer

Simulation of UV photodissociation of I2−(CO2)n: Spin-orbit quenching via solvent mediated electron transfer

Ultrafast vectorial and scalar dynamics of ionic clusters: Azobenzene solvated by oxygen

Global Minimum‐Energy Structure and Spectroscopic Properties of I2.−⋅n H2O Clusters: A Monte Carlo Simulated Annealing Study

Contact Info

Product

Resources

About

Photodissociation, Recombination, and Electron Transfer in Cluster Ions: A Nonadiabatic Molecular Dynamics Study of I₂^-(CO₂)_n

Global Minimum‐Energy Structure and Spectroscopic Properties of I₂^.−⋅n H₂O Clusters: A Monte Carlo Simulated Annealing Study