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Title: Self‐Assembly of a Semiconductive and Photoactive Heterobimetallic Metal–Organic Capsule
Abstract

We report the synthesis of a novel metal–organic capsule constructed from six pyrogallol[4]arene macrocycles, which are switched together by 16 FeIIIand 16 CoIIions. This supramolecular structure is the first instance of a spheroidal heterometallic nanocage assembled through a one‐step metal–ligand coordination approach. This new assembly also demonstrates an important proof of concept through the formation of multiple heterometallic metal–metal interactions within the capsule framework. Photophysical and electrochemical studies of self‐assembled capsule films indicate their potential as semiconductors. These materials display unexpected photoelectric conversion properties, thus representing an emergent phenomenon in discrete metal–organic supramolecular assemblies.

 
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Award ID(s):
1825352
NSF-PAR ID:
10236550
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
60
Issue:
19
ISSN:
1433-7851
Page Range / eLocation ID:
p. 10516-10520
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    We report the synthesis of a novel metal–organic capsule constructed from six pyrogallol[4]arene macrocycles, which are switched together by 16 FeIIIand 16 CoIIions. This supramolecular structure is the first instance of a spheroidal heterometallic nanocage assembled through a one‐step metal–ligand coordination approach. This new assembly also demonstrates an important proof of concept through the formation of multiple heterometallic metal–metal interactions within the capsule framework. Photophysical and electrochemical studies of self‐assembled capsule films indicate their potential as semiconductors. These materials display unexpected photoelectric conversion properties, thus representing an emergent phenomenon in discrete metal–organic supramolecular assemblies.

     
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  2. Rationale

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    Methods

    Self‐assembled complexes were synthesized by reacting a bis(terpyridine) ligand exhibiting a 60odihedral angle between the two ligating terpyridine sites (T) with divalent Zn, Ni, Cd, or Fe. The products were isolated as (Metal2+[T])n(PF6)2nsalts and analyzed using IM‐MS after electrospray ionization (ESI) which produced several charge states from eachn‐mer, depending on the number of PF6ˉ anions lost upon ESI. Experimental Ω data, derived using IM‐MS, and computational Ω predictions were used to elucidate the size and architecture of the complexes.

    Results

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