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arXiv · 1512.07124

(C$_{4}$H$_{12}$N$_{2}$)[CoCl$_{4}$] -tetrahedrally coordinated Co$^{2+}$ without the orbital degeneracy

C. Decaroli·A. M. Arevalo-Lopez·C. H. Woodall·E. E. Rodriguez·J. P. Attfield·S. F. Parker·C. Stock
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Abstract

We report on the synthesis, crystal structure, and magnetic properties of a previously unreported Co$^{2+}$ $S={3 \over 2}$ compound, (C$_{4}$H$_{12}$N$_{2}$)[CoCl$_{4}$], based upon a tetrahedral crystalline environment. The $S={3 \over 2}$ magnetic ground state of Co$^{2+}$, measured with magnetization, implies an absence of spin-orbit coupling and orbital degeneracy. This contrasts with compounds based upon an octrahedral and even known tetrahedral Co$^{2+}$ based systems where a sizable spin-orbit coupling is measured. The compound is characterized with single crystal x-ray diffraction, magnetic susceptibility, infrared, and ultraviolet/visible spectroscopy. Magnetic susceptibility measurements find no magnetic ordering above 2 K. The results are also compared with the previously known monoclinic hydrated analogue.

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C. Decaroli, A. M. Arevalo-Lopez, C. H. Woodall, E. E. Rodriguez, J. P. Attfield, S. F. Parker, C. Stock. 2015-12-22. (C$_{4}$H$_{12}$N$_{2}$)[CoCl$_{4}$] -tetrahedrally coordinated Co$^{2+}$ without the orbital degeneracy. https://doi.org/10.1107/s2052520614024809

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