On the Precise and Continuous Regulation of the Superatomic and Spectroscopic Behaviors of the Quasi-Cubic W4C4 Cluster by the Oriented External Electric Field

Designing and realizing novel superatoms with controllable and tunable electronic properties is vital for their potential applications in clusterassembly nanomaterials. Here, we investigated the effect of the oriented external electric field (OEEF) on the geometric and electronic structures as well as the spectroscopic properties of the quasi-cubic W4C4 cluster by utilizing the density functional theory (DFT) calculations. Compared with traditional models, the OEEF was observed to hold the special capability in continuously and precisely modulating the electronic properties of W4C4, that is, remarkably increasing its electron affinity (EA) (1.58 eV) to 5.61 eV under the 0.040 au OEEF (larger than any halogen atoms in the periodic table), which possesses the superhalogen behavior. Furthermore, the downward movement of the lowest unoccupied molecular orbital level of the cluster accompanied by the enhancement of the OEEF intensity was demonstrated to be the origin of the EA increment. Additionally, the photoelectron spectra (PES) of W4C4- were also simulated under different OEEF intensities, where the PES peaks move to a higher energy area following the enhancement of the OEEF strength, exhibiting the blue-shift behavior. These findings observed here open a new avenue in conveniently and precisely adjusting the electronic properties of clusters, which will be beneficial for the rational design of superatoms or superatom-assembled nanomaterials under the external field.

Automated summary

In this study, the effect of an oriented external electric field (OEEF) on the geometric and electronic structures as well as the spectroscopic properties of quasi-cubic W4C4 cluster was investigated using density functional theory (DFT) calculations. The OEEF was found to have the capability to continuously and precisely modulate the electronic properties of W4C4, exhibiting superhalogen behavior. Additionally, the downward movement of the lowest unoccupied molecular orbital level of the cluster accompanied by the enhancement of OEEF intensity was identified as the origin of the electron affinity increment. Moreover, the photoelectron spectra peaks of W4C4- shifted to higher energy areas with increasing OEEF strength, demonstrating blue-shift behavior.