MAGNETIC ANOMALIES IN POLYMERIC CHAIN COMPLEXES Cu(hfac)2 WITH SPIN-LABELED DIALKYLPYRAZOLES

• Published in: Journal of structural chemistry 2022, Vol.63 (1), p.87-99
• Main Authors: Romanenko, G. V., Fokin, S. V., Chubakova, E. T., Bogomyakov, A. S., Ovcharenko, V. I.
• Format: Article
• Language: English
• Subjects: Atomic; Atomic/Molecular Structure and Spectra; Chains (polymeric); Chemistry; Chemistry and Materials Science; Crystallography; Dynamic structural analysis; Inorganic Chemistry; Magnetic anomalies; Magnetic moments; Molecular; Optical and Plasma Physics; Physical Chemistry; Pyrazole; Solid phases; Solid State Physics; Temperature dependence
• ISSN: 0022-4766; 1573-8779
• DOI: 10.1134/S0022476622010103

The structures of hexafluoroacetylacetonate complexes of Cu(II)–Cu(hfac) 2 – with nitroxide radicals L R1/R2 , where R1 and R2 are alkyl substituents in the 1,3-pyrazole moiety are studied by X-ray crystallography. It is found that solid phases of all [Cu(hfac) 2 L R1/R2 ] are formed by polymeric chains whose common structural motif is a ditopic bridging coordination of paramagnetic ligands in the head-to-head fashion. The study of the temperature structure dynamics and the related change in the temperature dependence of the effective magnetic moment of the complex shows that changes in both R1 and R2 can substantially affect not only the possibility of the appearance of magnetic anomalies on the temperature curve of the effective magnetic moment but also its shape.