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Single molecule magnets (SMMs) are compounds that keep magnetization on the molecular scale, unlike conventional bulk magnets that exhibits collective long-range magnetic ordering. In view of above, SMMs have several potentional applications in many areas, the most promising one is high density fata storage. SMMs keep magnetization due to the presence of the magnetization reversal energy barrier U, caused by zero field splitting energy D. Since D has negative values in SMMs, the direct transition from Ms = -S to Ms = +S is forbidden by the selection rules. The greatest value of U among 3d metals-based SMMs are shown by Co(II) complexes[1]. The obtained dinucleur cobalt(II) complex has unusual geometry of the coordination polyhedron. It is intermediate between trigonal prism (TP) and trigonal antiprism (TAP). According to single crystal X-ray diffraction data, the distorsion angle is equal to 38o (while distorsion angles for TP and TAP are equal to 0o and 60o , respectively). Such complexes are very interesting for understanding of magnetostructural correlations for cobalt(II)-based SMMs [2]. For determination of electron structure of this complex we applied NMR spectroscopy and magnetometry, allowing to determine axial anisotropy (Δχax) and isotropic value of the magnetic susceptibility tensor. For room temperature Δχax = 0.05 A3 is strongly lower than for the both TP (0.26 A3 ) [3] and TAP (0.26 A3 ) [4] geometries. By comparison of NMR and magnetometry data for Co2L3 and similar CoZnL3 complexes we excluded exchange coupling between two Co+2 ions as origin of such low magnetic anisotropy. In this poster we will discussapplicationof NMR spectroscopy and magnetometry for electron structure study of the binuclear cobalt(II) complex.