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DOE OSTI · 1832699

Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes

Tripathi, Shalini·Vaidya, Shefali·Ahmed, Naushad·Andreasen Klahn, Emil·Cao, Huibo·Spillecke, Lena·Koo, Changhyun·Spachmann, Sven·Klingeler, Rüdiger·Rajaraman, Gopalan·Overgaard, Jacob·Shanmugam, Maheswaran
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Abstract

Stabilizing an easy axis of magnetization in an octahedral Co(II) complex is an extremely challenging task, which is evident from reports that more than 90% possess easy-plane anisotropy. Here, we report a six-coordinate complex, [Co(L 1 ) 4 (Cl) 2 ] (1, L 1 = thiourea [H 2 N-CS-NH 2 ]), that exhibits a D value of -63(10) cm -1 . The presence of an easy axis of magnetization associated with 1 is experimentally proven by detailed magnetic studies and polarized neutron diffraction studies, and the experimental observations are well corroborated by theoretical calculations. From the combined experimental and theoretical investigations (on 1 and many model systems), we unveil the parameters that control stabilization of negative D in a thermodynamically favorable and air-stable Co(II) ion in the common distorted octahedral geometry. This study paves the way for overcoming the current impediments to alleviate the easy axis of magnetization using rational ligand choice.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYORCAcobaltcoordination complexmagnetic anisotropymagnetismpolarized neutron diffractionsingle-molecule magnet

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Tripathi, Shalini, Vaidya, Shefali, Ahmed, Naushad, Andreasen Klahn, Emil, Cao, Huibo, Spillecke, Lena, Koo, Changhyun, Spachmann, Sven, Klingeler, Rüdiger, Rajaraman, Gopalan, Overgaard, Jacob, Shanmugam, Maheswaran. 2021-04-01. Structure-property correlation in stabilizing axial magnetic anisotropy in octahedral Co(II) complexes. https://doi.org/10.1016/j.xcrp.2021.100404

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