Direct Observation of Two-Dimensional Electron Solvation at Alcohol/Ag(111) Interfaces

Liu, S. H.; Miller, A. D.; Gaffney, Kelly J.; Szymanski, Paul; Garrett-Roe, Sean; Bezel, Ilya; Harris, Charles B.

doi:10.1021/jp025772r

Cited by 31 publications

(47 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Of particular interest has been the decoupling of the states from the metallic substrate by insulating spacers. The possibility to increase the lifetime in this way has been crucial for recent 2PPE experiments on the dynamics of localization due to small polaron formation [250,251] and electron solvation [252][253][254]. Likewise, in conventional photoemission work, rare-gas layers have been employed successfully to resolve the vibrational fine structure of 2D molecular layers [255][256][257].…”

Section: Decoupling By Spacer Layersmentioning

confidence: 99%

Decay of electronic excitations at metal surfaces

Echenique

Berndt

Chulkov

et al. 2004

Surface Science Reports

438

403

View full text Add to dashboard Cite

Section: Decoupling By Spacer Layersmentioning

confidence: 99%

Decay of electronic excitations at metal surfaces

Echenique

Berndt

Chulkov

et al. 2004

Surface Science Reports

438

403

View full text Add to dashboard Cite

“…22,23 A rotationally frustrated monolayer molecular dipole has been previously proposed to explain the low interfacial capacitance of DMSO measured by electrochemistry. The unifying physical process connecting bulk DMSO electrochemical capacitance to the dynamic energy relaxation measured in this experiment is molecular dipole reorientation.…”

Section: The Image Potential State As a Capacitancementioning

confidence: 99%

“…Knowledge of the probe photon energy, the electron 5 kinetic energy after photoemission and the time delay between pump and probe pulses provides the data to study the time dependence of the binding energy. 22,23 In 2PPE, the states populated by a UV pump are the hydrogenic progression of IPS's arising from the attractive, coulombic potential between an electron and the polarization it induces at a metal surface. The IPS binding energy is given by Equation 2:…”

Section: Introductionmentioning

confidence: 99%

“…This manifests itself as a dynamic, local workfunction shift induced by changes in the adsorbed layer. 22,24 Consequently, the IPS proves a useful probe of the layer's time-dependent dielectric response.…”

Section: Introductionmentioning

confidence: 99%

“…Estimates of plate area were made from earlier determinations of the coherence lengths of interfacial delocalized electrons (~100 Å) 22 and the ± 2σ width of a 17 Å FWHM Gaussian-shaped localized state. 28 This correction especially affects the 2 ML ε mol computation due to dynamic shrinkage of the model plate via electron localization.…”

mentioning

confidence: 99%

See 2 more Smart Citations

The Ultrafast Dynamics of Image Potential State Electrons at the Dimethylsulfoxide/Ag(111) Interface

et al. 2008

View full text Add to dashboard Cite

Angle-resolved two-photon photoemission was used to study the energy relaxation, population decay and localization dynamics of image potential state (IPS) electrons in ultrathin films of dimethylsulfoxide (DMSO) on an Ag(111) substrate. Dynamic energy shifts of 50 ± 10 meV and 220 ± 10 meV were observed for n=1 IPS electrons at one monolayer and two monolayer coverages of DMSO, respectively. The difference in energy shifts is attributed to rotational hindrance of the molecular dipole in the chemisorptive first monolayer. The finding confirms the proposed mechanism for the low differential capacitance of dimethylsulfoxide at noble metal interfaces in solution. A novel description of the IPS as a surface capacitance is presented to facilitate comparisons with electrochemical systems.

show abstract

Relaxation Dynamics in Image Potential States at Solid Interfaces

Johns¹,

Muller²,

Strader³

et al. 2010

Dynamics at Solid State Surfaces and Interfaces

View full text Add to dashboard Cite

The interface between metals and molecules remains an area of highly active research. The abrupt change in electronic environment between the electron gas of a metal and the covalent bonds of a molecule give rise to new surface states such as charge transfer excitons, metal-induced gap states (MIGS), and deep trap sites [1,2]. The behavior of electrons at these interfaces dominates both charge injection and charge collection in the growing number of molecular electronic devices. We have studied the dynamics and energetics of these interfacial states, specifically focusing on two particular states, the image potential state (IPS) and molecular based lowest unoccupied molecular orbitals (LUMOs).The image potential is the attractive potential that a charge feels near the surface of a conductor. An electron at the surface of metal induces a polarization in the metal, which exposes some of the underlying positive ionic cores. The actual shape of this polarization is quite complex inside the metal. Outside the metal, however, the potential is exactly that of a fictitious positive point charge placed inside the metal at a distance from the surface equal to that of the electron. This results in the classical 1/z distance-dependent form of the image potential. Quantum mechanically, this image potential can be solved analogously to a one-dimensional hydrogen atom, leading to a Rydberg-like series of bound states that converge to the vacuum level of the system.Electrons from inside the metal can be either directly or indirectly excited into these states upon exposure to ultraviolet (UV) light. For bare metal surfaces, the average distance from the surface of an electron in the first IPS (n ¼ 1, where n is the Rydberg quantum number) is on the order of 3 A . Energetically, the states are bound by 0.9-0.5 eV below the vacuum level, and decay via direct tunneling in under 50 fs. In the presence of a nonmetallic adsorbate, the IPS is partially screened by electrons in the adsorbate. The IPS can also hybridize with other molecular states at the interface, altering the energy of the state and changing the overlap of the IPS with the metal surface. In systems with strong electron-nuclear coupling such as organic molecules, the presence of an excess external charge can also lead to an induced nuclear motion that can further change the wave function and energy of the IPS. This makes

show abstract

Direct Observation of Two-Dimensional Electron Solvation at Alcohol/Ag(111) Interfaces

Cited by 31 publications

References 42 publications

Decay of electronic excitations at metal surfaces

Decay of electronic excitations at metal surfaces

The Ultrafast Dynamics of Image Potential State Electrons at the Dimethylsulfoxide/Ag(111) Interface

Relaxation Dynamics in Image Potential States at Solid Interfaces

Contact Info

Product

Resources

About