Coordination Behavior of 3‐Ethoxycarbonyltetronic Acid towards Cu(II) and Co(II) Metal Ions

Athanasellis, Giorgos; Zahariou, Georgia; Kikionis, Stefanos; Igglessi‐Markopoulou, Olga; Markopoulos, John

doi:10.1155/2008/547915

Cited by 6 publications

(2 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several studies of paramagnetic systems with spin of S = 3/2 have given evidence for the existence of EPR signals at various g eff values. − In principle, depending mainly on the magnitude of the zero-field splitting parameters in comparison to the microwave energy, EPR transitions take place either within the Kramers doublets, |±1/2⟩ and |±3/2⟩, or between them . Moreover, in many cases, both intra- and inter-doublet transitions take place, resulting in the presence of EPR signals at both low and high magnetic field region. , In order to examine whether the EPR signal at g eff ≈ 4 that was attributed to the high-spin S = 3/2 Co(II) species is accompanied by signals at lower g eff values, we performed EPR experiments similar to those described recently but at a wider magnetic field range.…”

Section: Resultsmentioning

confidence: 99%

Characterization of the High-Spin Co(II) Intermediate Species of the O₂-Evolving Co₄O₄ Cubic Molecules

Zahariou

2017

Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

An artificial oxygen-evolving complex (OEC) contains a tetranuclear CoO cubic cluster ligated with acetate and pyridine molecules, a light-activated Ru(bpy) moiety (bpy = 2,2'-bipyridine), and the sacrificial electron acceptor SO side. A recent EPR investigation of this system showed the formation of the high-spin Co(II) ion under visible-illumination conditions. It has been supported that this center originates from the cluster and is involved in the oxygen-evolving process. The present report is focused on the further characterization of the high-spin d configuration of the Co(II) species. The measurement of the EPR spectrum at a wider magnetic field range in comparison to that reported recently shows the presence of an additional signal that contributes to the spectrum of the Co(II) center. The theoretical simulation of this spectrum reveals that an isotropic g value and considerably small zero-field splitting parameters describe the high-spin Co(II) ion in a unique way, which supports a tetrahedral crystal field symmetry. On the basis of the spin-Hamiltonian parameters, the looping transitions that lead to the experimental EPR signals are determined. Additionally, a possible role of the symmetry of the Co(II) species and a proposed model that explains its formation during the O-evolving process of the CoO cubic molecules are discussed.

show abstract

Section: Resultsmentioning

confidence: 99%

Characterization of the High-Spin Co(II) Intermediate Species of the O₂-Evolving Co₄O₄ Cubic Molecules

Zahariou

2017

Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In the course of our research program on transition metal complexes with heterocyclic scaffolds containing the β -diketo functionality [ 21 – 23 ], we reported in a recent work the coordination model of tetronic acids with Cu (II) and Co (II) ions [ 10 , 24 ].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Crystal Structure Characterization of Zinc (II) Tetronic Acid Complexes

Prousis

Athanasellis

Stefanou

et al. 2010

Bioinorganic Chemistry and Applications

View full text Add to dashboard Cite

The synthesis and characterization of two new tetronic acid zinc (II) complexes of the empirical formulae [Zn(L–H)2(H2O)2] (1) and [Zn(L–H)2(H2O)(MeOH)]H2O (2) found within the same crystal are reported. The zinc ions bind through alkoxide and carbonyl groups of the ligand 3-methoxycarbonyl-5-phenyl tetronic acid (LH) as indicated by 1H NMR and X-ray crystallographic studies. These complexes promote intra- and intermolecular interactions, such as hydrogen bonding and π stacking, giving place to the formation of molecular aggregates.

show abstract

Hydrated‐Metal‐Halide‐Based Deep‐Eutectic‐Solvent‐Mediated NiFe Layered Double Hydroxide: An Excellent Electrocatalyst for Urea Electrolysis and Water Splitting

Zhang

Chen

Zhang

et al. 2019

Chemistry An Asian Journal

View full text Add to dashboard Cite

The liquid structures of deep eutectic solvents (DESs) based on hydrated metal halides and their application as electrolytes have been widely studied. However, little attention has been paid to the direct use of this type of DES in the preparation of micro‐/nanomaterials. Herein, an FeCl3⋅6 H2O/urea DES was used in the one‐step synthesis of NiFe‐LDH_D with a nanoflower morphology. In alkaline media, this catalyst promoted excellent electrocatalytic activity for the oxidation of urea at potential of 1.32 V (vs. RHE) and for the oxygen‐evolution reaction at a potential of 1.39 V to achieve a current density of 10 mA cm−2. These results were superior to the results with NiFe‐LDH/NF that was obtained from an aqueous solution of FeCl3, as well as most of the previously reported transition‐metal catalysts. Furthermore, NiFe‐LDH_D/NF could be readily implemented as both a cathode and an anode for the electrolysis of urea and water splitting. The use of hydrated‐metal‐halide‐based DESs for the preparation of LDH catalysts through a dipping‐redox strategy should both enrich the research of DESs and offer guidance for the rational surface engineering of catalysts for the electrolysis of urea and overall water splitting with high performance.

show abstract

Coordination Behavior of 3‐Ethoxycarbonyltetronic Acid towards Cu(II) and Co(II) Metal Ions

Cited by 6 publications

References 37 publications

Characterization of the High-Spin Co(II) Intermediate Species of the O₂-Evolving Co₄O₄ Cubic Molecules

Characterization of the High-Spin Co(II) Intermediate Species of the O₂-Evolving Co₄O₄ Cubic Molecules

Synthesis and Crystal Structure Characterization of Zinc (II) Tetronic Acid Complexes

Hydrated‐Metal‐Halide‐Based Deep‐Eutectic‐Solvent‐Mediated NiFe Layered Double Hydroxide: An Excellent Electrocatalyst for Urea Electrolysis and Water Splitting

Contact Info

Product

Resources

About

Coordination Behavior of 3‐Ethoxycarbonyltetronic Acid towards Cu(II) and Co(II) Metal Ions

Cited by 6 publications

References 37 publications

Characterization of the High-Spin Co(II) Intermediate Species of the O2-Evolving Co4O4 Cubic Molecules

Characterization of the High-Spin Co(II) Intermediate Species of the O2-Evolving Co4O4 Cubic Molecules

Synthesis and Crystal Structure Characterization of Zinc (II) Tetronic Acid Complexes

Hydrated‐Metal‐Halide‐Based Deep‐Eutectic‐Solvent‐Mediated NiFe Layered Double Hydroxide: An Excellent Electrocatalyst for Urea Electrolysis and Water Splitting

Contact Info

Product

Resources

About

Characterization of the High-Spin Co(II) Intermediate Species of the O₂-Evolving Co₄O₄ Cubic Molecules

Characterization of the High-Spin Co(II) Intermediate Species of the O₂-Evolving Co₄O₄ Cubic Molecules