Speaker
Dr
Anna Majcher
(Institute of Physics, Jagiellonian University, prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland)
Description
`We present a new approach to obtain functional magnetic materials: one that combines the qualities of polymers that are widely used to produce thin films, and Single Ion Magnets that exhibit magnetic relaxations.$^{[1]}$ By reactions of pyridine and 4-vinylpyridine with CoBr$_2$, we obtained two SIMs, showing field-induced relaxations of magnetization with energy barriers of 28(2) and 35(3) K, and $\tau_0$ values of $8\cdot 10^{-10}$ s and $1\cdot 10^{-11}$ s, respectively. Next, resulting from a reaction of poly(4-vinylpyridine) (P4VP), with its structural units identical to the ligands used to form the SIMs, with CoBr$_2$, a new material was formed with CoBr$_2$ bound to the pyridines within the polymer chains, forming a cross-linked macromolecular matrix. Field-induced relaxations of magnetization are preserved and dependent on the Co:P4VP structural units molar ratio, making it an amorphous semi-solid solution. Thin magnetic films were obtained by immersion of P4VP spin-cast films in CoBr$_2$ orthogonal solution. Atomic Force Microscopy (see figure, middle), Secondary Ion Mass Spectrometry and X-ray Photoelectron Spectroscopy confirm the binding of cobalt salts within the layer. AC magnetic measurements confirm the preservation of magnetic relaxations in the film. We believe that our research opens a new path that combines two fields of material research and is extremely promising regarding future applications of molecular magnets – as self-organizing macromolecular magnetic materials.`
`This research was financed by the Polish National Science Centre within the SONATA Project UMO-2015/19/D/ST5/01936.`
[1] G. A. Craig, M. Murrie, `$\textit{Chem. Soc. Rev.}$`, 2015, `$\textbf{44}$`, 2135-2147.
Primary author
Dr
Anna Majcher
(Institute of Physics, Jagiellonian University, prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland)
Co-authors
Dr
Andrzej Bernasik
(Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-049 Kraków, Poland)
Dr
Jakub Rysz
(Institute of Physics, Jagiellonian University, prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland)
Ms
Magdalena Ceglarska
(Institute of Physics, Jagiellonian University, prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland)
Dr
Mateusz M. Marzec
(Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, al. Mickiewicza 30, 30-049 Kraków, Poland)
Dr
Olaf Stefańczyk
(Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan)
Mr
Paweł Dąbczyński
(Institute of Physics, Jagiellonian University, prof. Stanisława Łojasiewicza 11, 30-348 Kraków, Poland)
Prof.
Shin-ichi Ohkoshi
(Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan)
