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Largely Enhancing the Blocking Energy Barrier and Temperature of a Linear Cobalt(II) Complex through the Structural
Fang Lu1, Wen-Xiao Guo1, Yi-Quan Zhang1
1Jiangsu Key Lab for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, P. R. China.
Abstract:
Complete-active-space self-consistent field and N-electron valence second-order perturbation theory have both been employed to investigate the magnetic anisotropy of one two-coordinate cobalt(II) compound via altering the Co-C bond lengths and twist angle φ. The calculated energy barrier Ueff decreases with the decrease in the Co-C bond lengths due to the gradually increasing interaction between the 3d orbitals of CoII and the coordination ligand field and then to the decrease in the ground orbital angular moment L of CoII. Thus, we cannot improve Ueff simply by shortening the Co-C bond lengths. However, by rotating the twist angle φ from 60 to 0°, it is surprising to find that the energy barrier and blocking temperature can be enhanced up to 1559.1 cm-1 and 90 K, respectively, with φ = 0°, which are prominent even among lanthanide-based single-molecule magnets.
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