Lithium doped tubular structure in LiB 20 and LiB 20 - : a viable global minimum

• Published in: Physical chemistry chemical physics : PCCP Vol. 20; no. 23; pp. 16202 - 16208
• Main Authors: Liang, Wei-Yan, Das, Anita, Dong, Xue, Cui, Zhong-Hua
• Format: Journal Article
• Language: English
• Published: England 04.06.2018
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/C8CP01376D

We present a strategy by which the stability of tubular boron clusters can be significantly enhanced by doping the B20 cluster with a lithium atom. High-level quantum chemical calculations showed that the lowest energy structures of LiB20 and LiB20- are tubular structures with D10d symmetry, in which the lithium atom is located at the center of the tubular structure. Chemical bonding analysis revealed that the high-symmetry tubular boron clusters are characterized as charge transfer complexes (Li+B20- and Li+B202-), resulting in double aromaticity with delocalized π + σ bonding and strong electrostatic interactions between cationic Li+ and tubular boron motifs with twenty Li-B interactions. The unique bonding pattern of the LiB20 and LiB20- species provides a key driving force to stabilize tubular structures over quasi-planar structures, suggesting that electrostatic interactions resulting from alkali metals might unveil a new clue to the structural evolution of boron clusters.