Planar B38-and B37-clusters with a double-hexagonal vacancy: molecular motifs for borophenes.
Boron clusters have been found to exhibit a variety of interesting electronic, structural, and bonding properties. Of particular interest are the recent discoveries of the 2D hexagonal B36-/0which led to the concept of borophenes and the 3D fullerene-like B40-/0which marked the onset of borospherene chemistry. Here, we present a joint photoelectron spectroscopic and first-principles study of B37-and B38-, which are in the transition size range between the 2D borophene-type clusters and the 3D borospherenes. These two clusters are found to possess highly stable 2D global-minimum structures consisting of a double-hexagonal vacancy. Detailed bonding analyses reveal that both B37-and B38-are all-boron analogues of coronene (C24H12) with a unique delocalized π system, featuring dual π aromaticity. These clusters with double hexagonal vacancies can be viewed as molecular motifs for the χ3-borophene which is the most stable form of borophenes recently synthesized on an Ag(111) substrate.
Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. hj.zhai@sxu.edu.cn lisidian@sxu.edu.cn and Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China and Institute of Materials Science, Xinzhou Teachers' University, Xinzhou 034000, China.
Qiang
Q
Chen
Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA. lai-sheng_wang@brown.edu.
Wen-Juan
WJ
Tian
Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. hj.zhai@sxu.edu.cn lisidian@sxu.edu.cn.
Lin-Yan
LY
Feng
Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. hj.zhai@sxu.edu.cn lisidian@sxu.edu.cn.
Hai-Gang
HG
Lu
Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. hj.zhai@sxu.edu.cn lisidian@sxu.edu.cn.
Yue-Wen
http://orcid.org/0000-0002-0162-5091
YW
Mu
Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. hj.zhai@sxu.edu.cn lisidian@sxu.edu.cn.
Hua-Jin
HJ
Zhai
Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. hj.zhai@sxu.edu.cn lisidian@sxu.edu.cn.
Si-Dian
http://orcid.org/0000-0001-5666-0591
SD
Li
Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA. lai-sheng_wang@brown.edu.
Lai-Sheng
LS
Wang