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Title: Chlorine dioxide: An exception that proves the rules of localized chemical bonding

We employ natural bond orbital and natural resonance theory tools to analyze the enigmatic properties of the C2v-symmetric isomer of chlorine dioxide radical (ClO2), whose many challenges to Pauling-type localized bonding concepts were recognized by Linus Pauling himself. Although spin-contamination is minimal in this species, ClO2exhibits an unusually strong form of “different Lewis structures for different spins” bonding pattern, intrinsically outside the framework of “maximal pairing” concepts. We show how the novel spin-unpaired donor–acceptor interactions lead to weakened bonding in the supramolecular domain of polyradical (ClO2)nhomoclusters and aqueous ClO2(H2O)nheteroclusters. Despite feeble binding energies and large inter-radical separations, the polyradical clusters are found to maintain coherent spin patterns in each cluster component, attesting to the quantal donor–acceptor nature of their interactions and the cooperative and anticooperative couplings that govern intra- and intermolecular spin distributions in such spin-clusters.

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Author(s) / Creator(s):
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
The Journal of Chemical Physics
Page Range / eLocation ID:
Article No. 124303
Medium: X
Sponsoring Org:
National Science Foundation
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