Formation and Spectroscopic Manifestation of Silver Clusters on Silver Bromide Surfaces

Marchetti, Alfred P.; Muenter, Annabel A.; Baetzold, R. C.; Mccleary, R. T.

doi:10.1021/jp980729i

Cited by 38 publications

(38 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…9 no significant population transfer occurs from the excited states to the ground state within the 2 ps of simulation time allowing us to estimate that the Ag 8 cluster will exhibit very long excited-state lifetimes. This finding is consistent with the experimental result that small silver clusters are strongly fluorescent in media such as argon matrices, surfaces or biolomolecular environment [19,[52][53][54][55].…”

Section: B Coupled Electron-nuclear Dynamics and Time-resolved Harmosupporting

confidence: 92%

Simulation of laser-induced coupled electron-nuclear dynamics and time-resolved harmonic spectra in complex systems

Lisinetskaya

Mitrić

2011

Phys. Rev. A

View full text Add to dashboard Cite

We present a theoretical approach for the simulation of time-resolved harmonic spectra, including the effect of nuclear dynamics, which is applicable to complex systems involving many nuclear degrees of freedom. The method is based on the combination of our semiclassical field-induced surface hopping approach for the treatment of laser-induced nuclear dynamics with the time-dependent density functional theory for electron dynamics. We apply our method to the simulation of ultrafast nonadiabatic dynamics and time-resolved harmonic spectra in small silver clusters (Ag 2 and Ag 8 ), which exhibit discrete molecularlike electronic transitions. We demonstrate that the harmonic signal is highly sensitive to the nuclear dynamics and thus can be used as a probe of coupled electron-nuclear dynamics, which is complementary to common pump-probe methods such as time-resolved photoelectron spectroscopy. Our simulations allowed us also to determine the mechanism and the time scale of nonradiative relaxation in the "magic" Ag 8 cluster and have provided a fundamental insight into ultrafast dynamics of metal nanoclusters in the size regime where "each atom counts." The excited-state dynamics of Ag 8 involves an isomerization process from the initial structure with T d symmetry to the quadratic antiprism structure with D 4d symmetry which takes place on a time scale of ∼600 fs and is clearly identified in a time-resolved harmonic signal. Our theoretical approach is generally applicable for the prediction of time-resolved harmonic spectra in complex systems with many nuclear degrees freedom and should serve to stimulate new ultrafast experiments utilizing harmonic signals as a probe for nonadiabatic processes in molecular systems.PHYSICAL REVIEW A 83, 033408 (2011)where χ (N) I (R,t) and χ (N−1) J (R,E,t) represent the nuclear wave packet in the bound and continuum states, respectively. 033408-4 SIMULATION OF LASER-INDUCED COUPLED ELECTRON-. . . PHYSICAL REVIEW A 83, 033408 (2011) (N) I (r; R) are the eigenfunctions of the N-electron Hamiltonian, while the antisymmetrized product A[ (N−1) J (r; R)φ J (E)] represents the continuum eigenfunctions of the combined ion-free electron Hamiltonian. In this product (N−1) J (r; R) is the J th cationic state and φ J (E) is a free electron scattering state. The summation extends over the whole range of singly ionized states. The wave-function ansatz in Eq. (17) can be inserted in the full electron-nuclear TDSE including the coupling to the electric field and a set of equations for the time evolution of the continuum portion of the nuclear wave packet of the ionized system χ (N−1) J (R,E,t) can be derived as ihχ (N−1) J (R,E,t) = T + E (N−1) J + E χ (N−1) J (R,E,t) − I ε(t) · µ I J (R,E)χ (N) I (R,t). (18) The semiclassical limit of this equation can be obtained by reducing the wave packet χ (N−1) J (R,E,t) to swarms of trajectories, as described previously [18]. This yields a set of equations for the time evolution of the amplitudes c (N−1) J (E,t) associated with each trajectory of a continu...

show abstract

Section: B Coupled Electron-nuclear Dynamics and Time-resolved Harmosupporting

confidence: 92%

Simulation of laser-induced coupled electron-nuclear dynamics and time-resolved harmonic spectra in complex systems

Lisinetskaya

Mitrić

2011

Phys. Rev. A

View full text Add to dashboard Cite

show abstract

“…As mentioned earlier, concerning the appreciably longer wavelength (∼475 nm) peak found in the diffuse reflectance studies, [10][11][12] Marchetti and co-workers suggested that it could be associated with rather heavily reduction-sensitized samples, not necessarily with Ag 2 dimers. 14 In light of our present result, however, we would rather suggest that liquid layers and coated ones may offer different dielectric environments for the Ag 2 molecules at room temperature, the former causing a further red shift in the transition energy. At least in the work of Hailstone and co-workers 11,12 the ∼475 nm absorption signal was so well-defined in a wide range of sensitizer concentrations that it is hard to assign the signal to any clusters other than Ag 2 molecules.…”

Section: Resultscontrasting

confidence: 56%

Diffuse Transmittance Spectroscopy of Diatomic Ag Nuclei on AgBr Microcrystals

Oku

Kawasaki

1998

J. Phys. Chem. B

View full text Add to dashboard Cite

A diffuse transmittance spectroscopy method that utilizes a large-area photodetector in contact with the sample is a simple and useful method to probe a weak light absorption by molecular species incorporated in a strongly scattering medium. The method successfully uncovered the electronic transition centered at 455 nm involving what are identified as diatomic Ag nuclei (Ag 2 ), which were size-selectively formed on a 0.45 µm octahedral AgBr microcrystal in a photographic emulsion in a surprisingly high density (many thousands on each microcrystal surface) through a heterogeneous chemical reduction. The estimated oscillator strength for the 455 nm absorption, 0.5 ( 0.1, compares favorably to the theoretical prediction (0.64) reported for the lowestenergy electronic transition of an isolated Ag 2 molecule, which is known to be centered at 435 nm. A possible mechanism underlying the remarkable size selectivity in the chemistry of Ag 2 formation on AgBr is also discussed in conjunction with a hypothetical (111) surface structure of the octahedral AgBr grain.

show abstract

“…As photosensitive materials, AgX and Ag/AgX (especially X = Cl and Br) are regarded as suitable semiconductor selections to modify photocatalytic composition system, which can produce efficient coupling photocatalysts with higher activity and stability compared with the single component [270][271][272][273][274][275][276]. Among them, the hybridization between AgX and other metallic semiconductor would significantly improve the light absorption efficiency and facilitate the photoinduced charge carrier separation with similar transmission routes [277][278][279][280][281][282][283][284][285][286]. Such as in TiO 2 coupling system, the spectral absorption range tuning of TiO 2 is the key factor for its visible light photocatalytic performance modification [287][288][289][290][291][292].…”

Section: Other Photoactive Semiconductormentioning

confidence: 99%

Regulations of silver halide nanostructure and composites on photocatalysis

Fan

Han

Song

et al. 2017

Adv Compos Hybrid Mater

View full text Add to dashboard Cite

The silver halides and their corresponding composites would constitute remarkable photocatalytic systems not only in energy production but also in environmental remediation. The major advantage in these silver halides system is that plasma metal Ag 0 species would be spontaneously generated by silver halides under light irradiation, which play dual roles of expanding light absorption range and charge carriers separation. In this tutorial review, the origin and development of silver halides, synthesis methods, construction of composite structures with other materials, photocatalytic applications, and various and controversial mechanisms are all exhaustively described.

show abstract

Formation and Spectroscopic Manifestation of Silver Clusters on Silver Bromide Surfaces

Cited by 38 publications

References 26 publications

Simulation of laser-induced coupled electron-nuclear dynamics and time-resolved harmonic spectra in complex systems

Simulation of laser-induced coupled electron-nuclear dynamics and time-resolved harmonic spectra in complex systems

Diffuse Transmittance Spectroscopy of Diatomic Ag Nuclei on AgBr Microcrystals

Regulations of silver halide nanostructure and composites on photocatalysis

Contact Info

Product

Resources

About