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Title: High‐Resolution Photoelectron Imaging of IrB 3 − : Observation of a π‐Aromatic B 3 + Ring Coordinated to a Transition Metal
Abstract

In a high‐resolution photoelectron imaging and theoretical study of the IrB3cluster, two isomers were observed experimentally with electron affinities (EAs) of 1.3147(8) and 1.937(4) eV. Quantum calculations revealed two nearly degenerate isomers competing for the global minimum, both with a B3ring coordinated with the Ir atom. The isomer with the higher EA consists of a B3ring with a bridge‐bonded Ir atom (Cs,2A′), and the second isomer features a tetrahedral structure (C3v,2A1). The neutral tetrahedral structure was predicted to be considerably more stable than all other isomers. Chemical bonding analysis showed that the neutralC3visomer involves significant covalent Ir−B bonding and weak ionic bonding with charge transfer from B3to Ir, and can be viewed as an Ir–(η3‐B3+) complex. This study provides the first example of a boron‐to‐metal charge‐transfer complex and evidence of a π‐aromatic B3+ring coordinated to a transition metal.

 
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NSF-PAR ID:
10102115
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
131
Issue:
26
ISSN:
0044-8249
Page Range / eLocation ID:
p. 8969-8973
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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