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Updated: Feb 22, 2026

Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
Stabilization of Low-Valent Iron(I) in a High-Valent Vanadium(V) Oxide Cluster
Montaha H Anjass1,2, Katharina Kastner1, Florian Nägele2
1Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
Abstract:
Low-valent iron centers are critical intermediates in chemical and bio-chemical processes. Herein, we show the first example of a low-valent FeI center stabilized in a high-valent polyoxometalate framework. Electrochemical studies show that the FeIII -functionalized molecular vanadium(V) oxide (DMA)[FeIII ClVV12 O32 Cl]3- (DMA=dimethylammonium) features two well-defined, reversible, iron-based electrochemical reductions which cleanly yield the FeI species (DMA)[FeI ClVV12 O32 Cl]5- . Experimental and theoretical studies including electron paramagnetic resonance spectroscopy and density functional theory computations verify the formation of the FeI species. The study presents the first example for the seemingly paradoxical embedding of low-valent metal species in high-valent metal oxide anions and opens new avenues for reductive electron transfer catalysis by polyoxometalates.
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