The tunneling current from a scanning microscope was used to image and dissociate single ${\mathrm{O}}_{2}$ molecules on the Pt(111) surface in temperature range of 40 150 K. After dissociation, two oxygen atoms are found one three lattice constants apart. dissociation rate as function vary ${I}^{0.8\ifmmode\pm\else\textpm\fi{}0.2}$, ${I}^{1.8\ifmmode\pm\else\textpm\fi{}0.2}$, ${I}^{2.9\ifmmode\pm\else\textpm\fi{}0.3}$ for sample biases 0.4, 0.3, 0.2 V, respectively. These rates explained...

We present a density functional theory study of water adsorption on metal surfaces. Prototype structures including monomers, clusters, one-dimensional chains, and overlayers have been investigated in detail model system---a Pt(111) surface. The structure, energetics, vibrational spectra are all obtained compared with available experimental data. This is further extended to other surfaces Ru(0001), Rh(111), Pd(111), Au(111), where monomers bilayers has investigated. From these studies,...

The adsorption of water on Pt(111) surface has been studied with ab initio molecular dynamics simulation. Both the energetics and vibrational indicate existence a well-ordered bilayer this surface. This conclusion is in contrast to recent result Ru(0001) surface, but agrees available experiments. In addition, our calculation identifies two different hydrogen bonds bilayer. can be directly recognized from spectra OH stretch modes.

The existence and nature of end central plasmon resonances in a linear atomic chain, the 1D analog to surface bulk plasmons 2D metals, has been predicted by ab initio time-dependent density functional theory. Length dependence absorption spectra shows emergence development collectivity these resonances. It converges single resonance longitudinal mode, two transverse resonances, which are localized at ends center atom chains. These collective modes bridge gaps, concept scale, between...

Electronic excitations in linear atomic chains of simple and noble metals (silver) have been studied using time-dependent density-functional theory. The formation development collective resonances the absorption spectra were obtained as functions chain length. A longitudinal resonance appears both simple- noble-metal chains. Its dispersion has deduced is compared with that a one-dimensional electron gas. transverse excitation generally shows bimodal structure, which can be assigned ``end...

Emission of photoexcited hot electrons from plasmonic metal nanostructures to semiconductors is key a number proposed nanophotonics technologies for solar harvesting, water splitting, photocatalysis, and variety optical sensing photodetector applications. Favorable materials catalytic properties make systems based on gold TiO2 particularly interesting, but the internal photoemission efficiency visible light low because wide bandgap semiconductor. We investigated incident photon-to-electron...

The calculated formation energies indicate that CsBr(MAI)-terminated 2D perovskites are more stable than PbBr₂(PbI₂)-terminated structures and an MAI-terminated monolayer could be even MAPbI₃ bulk.

The past decade has witnessed numerous discoveries of two-dimensional (2D) semimetals and insulators, whereas 2D metals are rarely identified. Borophene, a monolayer boron sheet, recently emerged as perfect metal with unique structure electronic properties. Here we study collective excitations in borophene, which exhibit two major plasmon modes low damping rates extending from infrared to ultraviolet regime. anisotropic 1D originates tilted Dirac cones analogous that heavily doped...

We present and discuss in detail a theory for atom transfer (or bond breaking) using the tip of scanning tunneling microscope that was outlined by us [Solid State Commun. 84, 271 (1992)]. The is applied to an atomic switch [Nature 352, 600 (1991)]. In this broken overcoming associated potential barrier thanks gain energy from electrons. crossing described truncated harmonic oscillator inelastic electron modeled simple resonance model electronic structure. rate shown be Arrhenius-like with...

The coupling of optical excitation and electron transport through a sodium atom in plasmonic dimer junction is investigated using time-dependent density functional theory. absorption dynamic conductance determined as function gap size. Surface plasmons are found to couple atomic-scale several different channels including dipolar, multipolar, charge transfer plasmon modes. These findings provide insight into subnanoscale couplings atoms, subject general interest plasmonics molecular electronics.

The formation of a Schottky barrier at the metal-semiconductor interface is widely utilised in semiconductor devices. With emerging novel based nanoelectronics, further microscopic understanding this high demand. Here we provide an atomistic insight into potential and band bending by ab initio simulations model analysis prototype diode, i.e., niobium doped rutile titania contact with gold (Au/Nb:TiO2). local height found to vary between 0 1.26 eV depending on position dopant. caused dopant...

Plasmon-induced electron-hole separation at metal-semiconductor interfaces is an essential step in photovoltaics, photochemistry, and optoelectronics. Despite its importance fundamental understandings technological applications, the mechanism dynamics of charge under plasmon excitations have not been well understood. Here, plasmon-induced between a Ag20 nanocluster TiO2(110) surface investigated using time-dependent density functional theory simulations. It found that consists two processes:...

A Lindblad operator is proposed to describe quantum dynamics of an open system with linear dissipation. Its functional form determined based on the microscopic Caldeira-Leggett model. It yields a new master equation which preserves positive density evolution short times and approaches equilibrium at high low temperatures. The applied as example study femtosecond vibrational relaxation desorption metal surface.

Plasmon opens up the possibility to efficiently couple light and matter at sub-wavelength scales. In general, plasmon frequency is dependent of carrier density. This dependency, however, renders fundamentally a weak intensity low frequency, especially for Dirac (DP) widely studied in graphene. Here we demonstrate new type DP, excited by nodal-surface state, which exhibits an anomalously density-independent frequency. Remarkably, predict realization anomalous DP (ADP) 1D topological...

Hot carriers generated by plasmonic damping have been suggested to promote photocatalysis, yet it remains unclear how the nonthermalized hot dynamically activate and energy transfer processes. Here, we present an Anderson-Newns model describe vibrational excitation bond dissociation induced carriers. The nonthermal distribution of plasmon is accounted for on equal footing with thermal at a given temperature in electron-molecule scattering. We found that electrons high region can, albeit much...

A molecular picture of hydrophilic and hydrophobic interactions, which ubiquitously exist in nature, has been proposed based on ab initio density functional study water at two prototype metal (Pt Au) surfaces. We demonstrate that the hydrophilicity–hydrophobicity can be characterized by water–surface coupling strength hydrogen bond interfaces. From this picture, Pt is found to while Au hydrophobic, agreement with experiment. The effect charge transfer long-ranged electron polarization these...

We present a theoretical study of collective plasmon excitation in metal thin films using the jellium model. The spectra are calculated linear response theory and time-dependent local density approximation. evolution from surface plasmons at large thickness to hybridized film smaller is obtained as functions atomic layers electron momenta. energies follow qualitatively classical electrodynamical model intermediate thickness. For ultrathin with few layers, these resonances evolve into...

A quantum kinetic theory of surface bond-breaking induced by laser-excited hot electrons is presented within a vibrational-heating mechanism, in which the fast electron-vibration energy transfer leads to heating and breaking local bond on femtosecond scale. The consists two related parts. first part discusses generally validity Pauli master equation describing dynamics vibrational reaction. Starting from Liouville-equation formalism density matrix, general derived for reduced distribution...

The velocity distribution of ${\mathrm{O}}_{2}$ photodesorbed from Pt(111) by femtosecond laser pulses is found to be approximately Maxwellian in form, with a translational temperature that increases fluence. Time-resolved measurements using two-pulse correlation scheme reveal subpicosecond response the temperature. These results are consistent desorption process driven multiple electronic transitions, where time-dependent substrate influences desorbing molecules.

A semiclassical model is developed to describe plasmon-electron coupling and electronic damping of surface plasmons. It compared with the ab initio linear response calculations for metallic thin films in jellium approximation a realistic crystalline Mg(0001) surface. The able reproduce quantum oscillations plasmon linewidth, which was obtained previous calculations. In addition, state-resolved analysis reveals origin these oscillations, result from superposition short-period individual...