Modes of phosphate binding to copper(II): investigations of the electron spin echo envelope modulation of complexes on surfaces and in solutions

Unusual 31P Hyperfine Strain Effects in a Conformationally Flexible Cu(II) Complex Revealed by Two-Dimensional Pulse EPR Spectroscopy

“…As this complex contains P atoms in its second coordination sphere, the hyperfine interactions (hfi) between the unpaired electron and the I = 1/2 nuclei of its 31 P atoms were investigated by Hyperfine Sublevel Correlation (HYSCORE) spectroscopy. This type of studies has been reported by Dikanov and co-workers for S = 1/2 vanadyl complexes bearing phosphate groups, − as well as by Chiesa and co-workers for vanadyl and Ti­(III) sites incorporated in molecular sieves. − Similar HYSCORE studies on Cu­(II) systems containing P ligand atoms are rather scarce. , The determination of hfi of the 31 P atoms of complex 1 is particularly useful in terms of investigating, by EPR methods, possible interactions between Cu­(II) and 31 P nuclei in analogous structures in which the 31 P atoms are also located in the second coordination sphere. Surprisingly, our results revealed not only “boomerang” line shapes, a term introduced recently by Dikanov and co-workers to describe a -strain effects, , but also spectral features that could not be reproduced by numerical simulations assuming only one set of hfc.…”

“…25−28 Similar HYSCORE studies on Cu(II) systems containing P ligand atoms are rather scarce. 29,30 The determination of hfi of the 31 P atoms of complex 1 is particularly useful in terms of investigating, by EPR methods, possible interactions between Cu(II) and 31 P nuclei in analogous structures in which the 31 P atoms are also located in the second coordination sphere. Surprisingly, our results revealed not only "boomerang" line shapes, a term introduced recently by Dikanov and co-workers to describe a-strain effects, 31,32 but also spectral features that could not be reproduced by numerical simulations assuming only one set of hfc.…”

Binary Doping of Strontium and Copper Enhancing Osteogenesis and Angiogenesis of Bioactive Glass Nanofibers while Suppressing Osteoclast Activity

“…The pristine undoped bioactive glass nanofibers were partially covered with apatite, while the doped glass fibers were sparsely mineralized in the order 50% Sr < (0.5% Cu + 50% Sr) < (1% Cu + 50% Sr). The retarded biomineralization in the case of Cu-doped glass fibers can be rationalized from the Lewis acid character of Cu 2+ and their binding affinity to phosphates, thus reducing apatite formation . On day 7, the pristine bioactive glass nanofibers (without Sr and/or Cu doping) were completely covered by flaky hydroxyapatite (HAp) (Figure A3), while the doped fibers were partially covered with minerals (Figure B3–D3).…”

Phosphate tuned copper electrodeposition and promoted formic acid selectivity for carbon dioxide reduction

“…[39][40][41] Phosphate anions interact with Cu(II) forming complexes in aqueous solution. [42][43][44] The thermodynamically possible complexes are Cu(HPO 4 ) 0 , Cu(H 2 PO 4 ) + , sparingly soluble precipitates [ [42][43][44][45][46] The formation of complexes leads to a decrease in free Cu(II) ions in the solution. If Cu electrodeposition is done in the presence of phosphate anions, one could hypothesize that a chemical equilibrium will be attained between the free Cu(II) ions and formed complexes.…”