View in EDS

Trigonal prismatic coordination geometry imparted by a macrocyclic ligand: an approach to large axial magnetic anisotropy for Co(II).

Saved in:
Bibliographic Details
Title: Trigonal prismatic coordination geometry imparted by a macrocyclic ligand: an approach to large axial magnetic anisotropy for Co(II).
Authors: Zahradníková, Eva1 (AUTHOR), Sutter, Jean-Pascal2 (AUTHOR) jean-pascal.sutter@lcc-toulouse.fr, Halaš, Petr1 (AUTHOR), Drahoš, Bohuslav1 (AUTHOR) bohuslav.drahos@upol.cz
Source: Dalton Transactions: An International Journal of Inorganic Chemistry. 12/28/2023, Vol. 52 Issue 48, p18513-18524. 12p.
Subjects: Magnetic anisotropy, Single molecule magnets, Magnetic susceptibility, Geometry
Abstract: Large uniaxial magnetic anisotropy, expressed by a negative value of the axial zero-field splitting parameter D, has been achieved in a series of trigonal prismatic Co(II) complexes with the general formula [Co(L)X]Y, where L = 1,5,13,17,22-pentaazatricyclo[15.2.2.17,11]docosa-7,9,11(22)-triene, X = Cl−(1a,b), Br−(2), N3−(3), NCO−(4), NCS−(5), NCSe−(6), and Y = Cl−(1), Br−(2), NCS−(4), NCSe−(5), ClO4−(3,6). Complexes 1–6 are six-coordinate with the distorted trigonal prismatic geometry imparted by the pentadentate pyridine-/piperazine-based macrocyclic ligand L and by one monovalent coligand X−. Based on magnetic studies, all complexes 1–6 exhibit strong magnetic anisotropy with negative D-values ranging from about −20 to −41 cm−1. This variation in D (i.e. the increase of magnetic anisotropy) parallels the trend obtained by theoretical calculations and the lesser distortion of the coordination sphere with respect to the trigonal prismatic reference geometry. AC magnetic susceptibility investigations revealed field-induced single-molecule magnet behaviour for all complexes except Cl− derivative 1. The series investigated represents a rare example of Co(II) complexes with a robust trigonal prismatic geometry. [ABSTRACT FROM AUTHOR]
Copyright of Dalton Transactions: An International Journal of Inorganic Chemistry is the property of Royal Society of Chemistry and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:Large uniaxial magnetic anisotropy, expressed by a negative value of the axial zero-field splitting parameter D, has been achieved in a series of trigonal prismatic Co(II) complexes with the general formula [Co(L)X]Y, where L = 1,5,13,17,22-pentaazatricyclo[15.2.2.17,11]docosa-7,9,11(22)-triene, X = Cl−(1a,b), Br−(2), N3−(3), NCO−(4), NCS−(5), NCSe−(6), and Y = Cl−(1), Br−(2), NCS−(4), NCSe−(5), ClO4−(3,6). Complexes 1–6 are six-coordinate with the distorted trigonal prismatic geometry imparted by the pentadentate pyridine-/piperazine-based macrocyclic ligand L and by one monovalent coligand X−. Based on magnetic studies, all complexes 1–6 exhibit strong magnetic anisotropy with negative D-values ranging from about −20 to −41 cm−1. This variation in D (i.e. the increase of magnetic anisotropy) parallels the trend obtained by theoretical calculations and the lesser distortion of the coordination sphere with respect to the trigonal prismatic reference geometry. AC magnetic susceptibility investigations revealed field-induced single-molecule magnet behaviour for all complexes except Cl− derivative 1. The series investigated represents a rare example of Co(II) complexes with a robust trigonal prismatic geometry. [ABSTRACT FROM AUTHOR]
ISSN:14779226
DOI:10.1039/d3dt02639f