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Covalent Co-O-V and Sb-N Bonds Enable Polyoxovanadate Charge Control.

ABSTRACT: The formation of [{CoII(teta)2}{CoII2(tren)(teta)2}VIV15SbIII6O42(H2O)]·ca.9H2O [teta = triethylenetetraamine; tren = tris(2-aminoethyl)amine] illustrates a strategy toward reducing the molecular charge of polyoxovanadates, a key challenge in their use as components in single-molecule electronics. Here, a V-O-Co bond to a binuclear Co2+-centered complex and a Sb-N bond to the terminal N atom of a teta ligand of a mononuclear Co2+ complex allow for full charge compensation of the archetypal molecular magnet [V15Sb6O42(H2O)]6-. Density functional theory based electron localization function analysis demonstrates that the Sb-N bond has an electron density similar to that of a Sb-O bond. Magnetic exchange coupling between the VIV and CoII spin centers mediated via the Sb-N bridge is comparably weakly antiferromagnetic.

SUBMITTER: Rasmussen M

PROVIDER: S-EPMC5696651 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Covalent Co-O-V and Sb-N Bonds Enable Polyoxovanadate Charge Control.

Rasmussen Maren M Näther Christian C van Leusen Jan J Kögerler Paul P Zhechkov Lyuben L Heine Thoma T Bensch Wolfgang W

Inorganic chemistry 20170525 12

The formation of [{CoII(teta)2}{CoII2(tren)(teta)2}VIV15SbIII6O42(H2O)]·ca.9H2O [teta = triethylenetetraamine; tren = tris(2-aminoethyl)amine] illustrates a strategy toward reducing the molecular charge of polyoxovanadates, a key challenge in their use as components in single-molecule electronics. Here, a V-O-Co bond to a binuclear Co2+-centered complex a ...[more]

PMID: 28541697

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