The structural and electronic properties of tubular gold clusters with a spinal support

Abstract

Scalar relativistic density functional theory (DFT) is used to investigate the structural and electronic properties of an endohedrally doped hollow tube of gold with a hexagonal cross-section, X(M)Au(N) (X = Si, Al and Au, M = 3, 6, 9 and N = 24, 42, 60). Only Si as a dopant can be encapsulated to provide a stable backbone to the parent tubular Au(N) whereas structures containing an Al or Au backbone are distorted into non-cage like structures as the size increases. The dopant atoms increase the electron density around the Fermi level and shift the d-energy levels to deeper energy levels, thus reducing the HOMO–LUMO gap of the AuN tube. The effect is more pronounced in the Si doped Au(N) than the Al or Au doped Au(N) tubes. The Si9Au60 structure, though stable, shows a slight bending which can be corrected by removing one Si atom from the backbone which provides it with the correct amount of space. It can be concluded that Si and Al atoms can form long chains within the Au nanotube if a gap is present after every 4–6 layers of Au atoms to accommodate the size mismatch between the Si–Si and Al–Al bonds and the Au layers. Si doping within the Au(N) tube is more compatible than Al doping, as confirmed by Mulliken charge analysis.

Thermo-Stimuli Response of Doped MAun– Clusters (n = 4–8; M = Si, Ge) at Discrete Temperatures: A BOMD Undertaking

“…Accordingly, Si doping in gold clusters is most widely studied using theoretical methodologies. − Manzoor et al recently studied the effect of doping with Si on the reactivity of Au 7 0 cluster. They found that the presence of a Si atom within a Au cluster not only enhances the O 2 activation on Au 7 0 but also significantly reduces the activation barrier toward the formation of CO 2 from CO and O 2 .…”

Doped golden fullerene cages

“…15,16 The surge of interest in hollow nanostructures, together with the wide range of possibilities offered by nanoalloys with respect to elemental clusters, 17 has led recently to the study of bimetallic cages. [18][19][20][21] However, these studies are often limited to the investigation of a single metal atom encapsulated into a golden cage, [22][23][24][25][26][27] whereas a systematic study of the stability of golden cages after doping with other metallic species is still missing.…”