Search

The electronic properties of the ternary potassium-ammonium graphite intercalation compound K(NH3)(sub 4)C24 are studied using generalized gradient-corrected density functional theory. This results in the K 4s electron being promoted to a very diffuse state extending in the outer region of the K(NH3)4 cluster, with the electron only loosely bound to the nearly planar K(NH3)(sub 4)(super +) system.

Time-resolved two-photon photoemission is utilized to study solvation dynamics at two-dimensional interfaces. Collective reorientation of a dipolar adsorbate in the presence of an image potential states electron results in dynamic reduction of the local work function, which is manifest in the observed dynamic changes of the photoelectron kinetic energies.

The electronic dynamics at the naphthalene/Ag(111) and the anthracene/Ag(111) interfaces are investigated with femtosecond time and angle resolved two photon photoemission. The results show that the transition from a near resonant to a non resonant interaction between the image potential and the adsorbate electron affinity levels causes significant variations in binding energies.

A study was conducted to investigate electron relaxation processes at metal surfaces in the presence of thin layers of insulating or wide energy gap materials. The experiment demonstrated that the perpendicular spatial extent of the electronic wavefunction at the interface primarily determines the inter-band relaxation rate of electrons or relaxation from the interfacial states to the metal bulk bands. Experimental results and implications are discussed.