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Interplay with Axial Halide Ligands (F-, Cl-, Br-) to Modulate or Switch the Magnetic Anisotropy in Octahedral
Naushad Ahmed1, Muneshwar Nandeshwar1, Prem Prakash Sahu2
1Organometallics and Materials Chemistry Lab, Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Hyderabad, Telangana, 502085, India.
None:
In this study, we intended to explore the role of axially coordinated halides (F-, Cl-, or Br-) to modulate the magnetic anisotropy of Co(II) ion in octahedral [CoII(LN2)2X2] {where X = Cl- (1), Br- (2), or F- (3opt) and LN2 = (E)-N-(2,6-dibenzhydryl-4-(trifluoromethoxy) phenyl)-1-(pyridin-2-yl)} complexes. The X-ray diffraction and structural elucidation revealed that 1 and 2 crystallized in tetragonal P4/n. The direct current (dc) magnetic susceptibility and magnetization data were collected and fitted or simulated to confirm the easy plane magnetic anisotropy for 1 and 2 with D = +28.5(1) cm-1 and + 47.8(1) cm-1, respectively. The alternating current (ac) magnetic susceptibility studies suggest field-induced SMM behaviors for 1 and 2. Theoretical studies on the X-ray structures of 1 and 2 further revealed the easy plane magnetic anisotropy, which strongly corroborated our experimental findings. The CASSCF predicted D value of -81.2 cm -1 for the modeled structure 3opt (having axial F-) indicates the switching of the easy plane to the easy axis of magnetic anisotropy.
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