The complexes of Cu2+ hexafluoroacetylacetonate with two pyrazol-substituted nitronyl nitroxides are the choice systems to study the spin dynamics of strongly exchange-coupled spin triads. The large values of exchange coupling (ca. 100 cm-1) and high-resolution electron paramagnetic resonance (EPR) at Q- and W-bands (35 and 94 GHz) allowed us to observe and interpret specific characteristics of these systems. An electron spin exchange process has been found between different multiplets of the spin triad, which manifests itself as a significant shift of the EPR line position with temperature. We propose that the spin exchange process is caused by the modulation of exchange interaction between copper and nitroxides by lattice vibrations. The estimations of the rate of exchange process and model calculations essentially support the observed phenomena. The studied characteristics of strongly coupled spin triads explain previously obtained results, agree with literature, and should be accounted for in future investigations of similar spin systems.
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Nanoscale
January 2025
Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA 94550, USA.
Quantum dots (QDs) are promising materials for optoelectronic applications, but their widespread adoption requires controllable, selective, and scalable deposition methods. While traditional methods like spin coating and drop casting are suitable for small-scale deposition onto flat substrates, and ink-jet printing offers precision for small areas, these methods struggle with conformal deposition onto non-planar, large area substrates or selective deposition onto large area chips. Electrophoretic deposition (EPD) is an efficient and versatile technique capable of achieving conformal and selective area deposition over large areas, but its application to QD films has been limited.
View Article and Find Full Text PDFNat Mater
January 2025
Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY, USA.
Spin waves, or magnons, are essential for next-generation energy-efficient spintronics and magnonics. Yet, visualizing spin-wave dynamics at nanoscale and microwave frequencies remains a formidable challenge due to the lack of spin-sensitive, time-resolved microscopy. Here we report a breakthrough in imaging dipole-exchange spin waves in a ferromagnetic film owing to the development of laser-free ultrafast Lorentz electron microscopy, which is equipped with a microwave-mediated electron pulser for high spatiotemporal resolution.
View Article and Find Full Text PDFJ Pharm Sci
January 2025
Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, FL, USA, 32310; Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, USA, 32310. Electronic address:
Monoclonal antibodies (mAb) represent an important class of biologic therapeutics that can treat a variety of diseases including cancer, autoimmune disorders or respiratory conditions (e.g. COVID-19).
View Article and Find Full Text PDFChemistry
January 2025
Jadavpur University, Chemistry, 188 Raja S. C. Mallick Road, 700032, Kolkata, INDIA.
Two π-radical complexes containing bisazo-aromatic-centered radical anion (1•-) were synthesized through in-situ electron transfer from metal-to-ligand using [IrI] and 2-(2-Pyridylazo)azobenzene (1) in inert hydrocarbon solvent. These are characterized as diradical [IrIII(1•-)2]+[2]+ and monoradical [IrIII(1•-)Cl2(PPh3)] 3. In contrast, a rare metal-mediated hydrolytic cleavage of the C(sp2)-N bond occurred in protic solvent resulting in quaternary radical complex [IrIII(1•-)(1')(PPh3)]+(4)+.
View Article and Find Full Text PDFDalton Trans
January 2025
School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, Jiangsu, China.
Five alkali metal manganese(III) fluorophosphates, KMn(POF)F (I), RbMn(POF)F (II), RbMn(POF)(PO)F (III), RbMn(POF)(PO)F (IV), and CsMn(POF)F (V), were successfully synthesized using a hydrothermal method. The monofluorophosphate anion (POF) groups work as "chemical scissors" to promote low-dimensional spin structures with the aid of alkali metal cations. I and II had an = 2 uniform chain structure formed by corner-sharing -MnOF octahedra.
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