Direct evidences of pentagonal silicon chains and magic clusters

TL;DR

This study provides direct visual and spectroscopic evidence of pentagonal silicon structures in nanoribbons and clusters, revealing their potential as fundamental elements in silicon-based nanoelectronics.

Contribution

It is the first to directly observe and chemically identify silicon pentagons in 1D nanostructures using advanced microscopy and spectroscopy techniques.

Findings

Visualization of silicon pentagon-ring structures in nanoribbons and clusters

Detection of silicon pentagon fingerprints via tip-enhanced Raman spectroscopy

Silicon pentagons could be key building blocks for future nanoelectronic devices

Abstract

Pentagon is one of the most beautiful geometric structures in nature, but it is rarely seen simply because five-fold symmetry is mathematically forbidden in a 2D or 3D periodic lattices. Fortunately, pentagon as a structural element is allowed in 1D or 0D systems, since translational symmetry is not necessary there. However, in these systems pentagons only compose a small portion of the structure. So far, 1D or 0D systems consisting of purely pentagons are still rare. Here, combing high resolution non-contact atomic force microscopy and tip-enhanced Raman spectroscopy, we have directly visualized the pentagon-ring structure in self-assembled Si nanoribbons and magic clusters on Ag(110) substrate. Moreover, chemical fingerprint of Si pentagon was detected in individual Si nanoribbon and clusters by tip-enhanced Raman spectroscopy. This work demonstrates that Si pentagon can be an important element in building silicon nanostructures, which may find potential applications in future nanoelectronics based on silicon.