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Title: B 48 − : a bilayer boron cluster
Size-selected negatively-charged boron clusters (B n − ) have been found to be planar or quasi-planar in a wide size range. Even though cage structures emerged as the global minimum at B 39 − , the global minimum of B 40 − was in fact planar. Only in the neutral form did the B 40 borospherene become the global minimum. How the structures of larger boron clusters evolve is of immense interest. Here we report the observation of a bilayer B 48 − cluster using photoelectron spectroscopy and first-principles calculations. The photoelectron spectra of B 48 − exhibit two well-resolved features at low binding energies, which are used as electronic signatures to compare with theoretical calculations. Global minimum searches and theoretical calculations indicate that both the B 48 − anion and the B 48 neutral possess a bilayer-type structure with D 2h symmetry. The simulated spectrum of the D 2h B 48 − agrees well with the experimental spectral features, confirming the bilayer global minimum structure. The bilayer B 48 −/0 clusters are found to be highly stable with strong interlayer covalent bonding, revealing a new structural type for size-selected boron clusters. The current study shows the structural diversity of boron nanoclusters and provides experimental evidence for the viability of bilayer borophenes.  more » « less
Award ID(s):
1763380
PAR ID:
10296221
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
13
Issue:
6
ISSN:
2040-3364
Page Range / eLocation ID:
3868 to 3876
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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