Structural and electronic properties of Al nanowires: an ab initio pseudopotential study

TL;DR

This study uses ab initio pseudopotential methods to analyze the structural stability and electronic properties of aluminum nanowires, revealing phase transitions, the role of 2p bands, and effects of density functionals.

Contribution

It provides new insights into the structural rearrangements, electronic structure evolution, and stability factors of Al nanowires, bridging theoretical models with experimental relevance.

Findings

Al wire undergoes zigzag structural rearrangements under compression

2p bands are crucial for nanowire stability

Density functional choice affects cohesive energy and bond length

Abstract

The stability and electronic structure of a single monatomic Al wire has been studied using the ab initio pseudopotential method. The Al wire undergoes two structural rearrangements under compression, i.e., zigzag configurations at angles of $140^o$ and $60^o$. The evolution of electronic structures of the Al chain as a function of structural phase transition has been investigated. The relationship between electronic structure and geometric stability is also discussed. The 2p bands in the Al nanowire are shown to play a critical role in its stability. The effects of density functionals (GGA and LDA) on cohesive energy and bond length of Al nanostructures (dimmer, chains, and monolayers) are also examined. The link between low dimensional 0D structure (dimmer) to high dimensional 3D bulk Al is estimated. An example of optimized tip-suspended finite atomic chain is presented to bridge the gap between hypothetical infinite chains and experimental finite chains.