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Title: A Triply Negatively Charged Nanographene Bilayer with Spin Frustration
Abstract

We report on the largest open‐shell graphenic bilayer and also the first example of triply negatively charged radical π‐dimer. Upon three‐electron reduction, bilayer nanographene fragment molecule (C96H24Ar6)2(Ar=2,6‐dimethylphenyl) (12) was transformed to a triply negatively charged species123.−, which has been characterized by single‐crystal X‐ray diffraction, electron paramagnetic resonance (EPR) spectroscopy and magnetic properties on a superconducting quantum interference device (SQUID).123.−features a 96‐center‐3‐electron (96c/3e) pancake bond with a doublet ground state, which can be thermally excited to a quartet state. It consists of 34 π‐fused rings with 96 conjugatedsp2carbon atoms. Spin frustration is observed with the frustration parameterf>31.8 at low temperatures in123.−, which indicates graphene upon reduction doping may behave as a quantum spin liquid.

 
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Award ID(s):
2107820
NSF-PAR ID:
10396076
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
8
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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