Wydział Chemii

Anna Świtlicka

Barbara Machura

Mateusz Penkala

Alina Bieńko

Dariusz C. Bieńko

Jan Titiš

Cyril Rajnák

Roman Boča

Andrew Ozarowski

Mykhaylo Ozerov

2018

Inorganic Chemistry

57

12740-12755

10.1021/acs.inorgchem.8b01906

Naukowa

Angielski

Artykuł

Three pentacoordinate complexes of the type [Co(pypz)X₂], where pypz is a tridentate ligand 2,6-bis(pyrazol-1-yl)pyridine and X = Cl^– (1), NCS^– (2), and NCO^– (3), have been synthesized, and their structures have been determined by X-ray analysis. The DC magnetic data show a sizable magnetic anisotropy, which was confirmed by high-field high-frequency electron paramagnetic resonance (HF EPR) measurements. Well-resolved HF EPR spectra of high spin cobalt (II) were observed over the microwave frequency range 100–650 GHz. The experimental spectra of both complexes were simulated with axial g tensor components, a very large positive D value, and different E/D ratios. To determine the exact D value for 2 (38.4 cm^–1) and 3 (40.92 cm^–1), the far-infrared magnetic spectroscopy method was used. Knowledge of the zero field splitting parameters and their signs is crucial in interpreting the single-molecule magnet or single chain magnet behavior. The AC susceptibility data confirm that these complexes exhibit a slow magnetic relaxation under small applied DC field with two (1 and 3) or three (2) relaxation modes.

http://doi.org/10.1021/acs.inorgchem.8b01906

https://www.acs.org/content/acs/en.html