Atomistic spectrometrics of local bond-electron-energy pertaining to Na and K clusters

Abstract

Consistency between density functional theory calculations and photoelectron spectroscopy measurements confirmed our predications on the undercoordination-induced local bond relaxation and core level shift of Na and K clusters. It is clarified that the shorter and stronger bonds between under-coordinated atoms cause local densification and local potential well depression and shift the electron binding-energy accordingly. Numerical consistency turns out the energy levels for an isolated Na (E2p=31.167eV) and K (E3p=18.034eV) atoms and their respective bulk shifts of 2.401eV and 2.754eV, which is beyond the scope of conventional approaches. This strategy has also resulted in quantification of the local bond length, bond energy, binding energy density, and atomic cohesive energy associated with the undercoordinated atoms.