The infrared HOMO–LUMO gap of germanium clusters

Ionization potentials, electron affinities, and vibrational frequencies of Gen (n=5–10) neutrals and charged ions from density functional theory

“…7 Electronic properties of these optimized structures including the relative orbital and total energies, I.P.s, and E.A.s are calculated with the same basis sets and compared with corresponding experimental values. 6,[9][10][11][12] Electronic property calculation is further performed at the optimized structures with a bigger basis of 6-311G(3d f ). The initial input structures are taken either from published results or arbitrarily constructed and fully optimized via the Berny algorithm.…”

“…Shvartsburg et al 10 proposed the geometries of Ge n and Ge n ϩ (nϽ17) recently using local density approximation ͑LDA͒ and the gradient-corrected method, but there were no experimental I.P.s to compare with at that time and frequency analyses were not performed in their calculations. Electron affinities ͑E.A.s͒ (nϭ1 -11) and HOMO-LUMO gaps (nϭ4 -32) of Ge n have also been bracketed with PES, 11,12 and again, there have been no adequate theoretical calculations made to explain these results. The main difference between the photoemission spectra of Si 10 Ϫ and Ge 10 Ϫ was first explained by Ogut et al 1 utilizing the Langevin molecular dynamics coupled to a simulated anneal-ing procedure using quantum forces derived from ab initio pseudopotentials constructed within the LDA scheme, but more accurate theoretical calculation, frequency analyses, and a stability check are required to confirm this explanation.…”

The nature of structure and bonding between transition metal and mixed Si‐Ge tetramers: A 20‐electron superatom system

“…Semiconductor silicon and germanium clusters are still an exciting research area and have been extensively investigated both experimentally and theoretically, because these clusters can act as a tunable building block to realize miniature nano‐devices by self‐assembly, with purpose to build up the novel nanomaterials applied in microelectronics industry . However, pure semiconductor clusters favor the sp 3 hybridization, and are chemically reactive due to the existence of unsaturated dangling bonds, resulting in the formation of unstable cage structures .…”

Geometric structures and electron affinities of chlorine-doped silicon clusters

“…Numerous experiments have been devoted to investigating the structures and stability of IV-VII mixed clusters. Negishi et al [16][17][18] have produced Si n F À m , Ge n F À m and Ge n Cl À m binary clusters using photoelectron spectroscopy (PES) with a magnetic-bottle-type electron spectrometer, and electron affinities are reported. C n Cl, C n Cl À , and C n Cl þ clusters have been studied theoretically [19] at the B3LYP/ 6-311G(d) level, and a systematic investigation of Si n F À and Si n F (n ¼ 1-7) clusters has been carried out [20] using ab initio MO methods.…”