Synthesis, Crystal Structures and Magnetic Properties of Mononuclear High-Spin Cobalt(II) Complex

Abstract

A new four-coordinated high-spin Co(II) complex was synthesized through the reactions of Co(NSC)2 with bathocuproine, by the diffusion method, resulting in an infinite one-dimension chain. Both static and dynamic magnetic properties were measured. The magnetic properties investigation shows that the single CoII ion properties dominate the magnetic behavior in the complex. Despite the presence of a four-coordinated single CoII ion, no SMM properties were exhibited by the complex.

Mononuclear High‐spin Octahedral Cobalt(II) Complex with Positive Axial Magnetic Anisotropy: Synthesis, Crystal Structure, and DFT Studies

“…The coordination sphere around cobalt(II) ion is surrounded by two thiocyanate N atoms in cis positions and equatorial plane is occupied by two tmphen N atoms while the remaining two imine N atoms occupy the axial positions. The Co–N thiocyanate bond lengths [average 2.062(3) Å] are rather shorter than the equatorial Co–N tmphen bond lengths [average 2.20(3) Å], which are in turn slightly larger than the axial Co–N bond lengths [average 2.153(3) Å], all of which are typical of high‐spin cobalt(II) ions, consistent with the previously reported cobalt(II) complex . The bond angle between N–Co–N bond connecting the two cis ‐thiocyanate groups is found to be 91.56(1)°, which is nearly equal to the bond angle 91.47(1)° between the two N atom from the tmphen ligand at an equatorial plane.…”

“…The stretching frequency ν(CN) of thiocyanate are lower in N‐bonded (near 2050 cm –1 ) than S‐bonded complexes (near 2100 cm –1 ). The ν(CN) observed at 2054 cm –1 in complex suggests that the pseudo‐halide is coordinated to cobalt through the nitrogen atom (terminal N‐bonded) . The relatively weak peak observed at 2863 cm –1 correspond to –CH stretching vibration while the sharp signal at 1409 cm –1 is due to –CH bending vibration of aromatic rings .…”

“…In continuation of our previous work on high‐spin mononuclear cobalt(II) complex, herein, we extend our efforts on development of magnetic behavior of newly synthesize mononuclear six‐coordinate cobalt(II) complex cis ‐[Co II (tmphen) 2 (NCS) 2 ], in which tmphen is the sterically hindered ligand 3,4,7,8‐tetramethyl‐1,10‐phenanthroline. For the purpose of elucidating the structural analysis of the magnetic properties, we have chosen thiocyanato‐κ N ligand due to its linearity and monodentate interaction mode, and thus will make room for flexibility in metal geometry.…”

“…Despite the significant advancements in this area, some features of SMM property that demonstrate fascinating physical properties are still growing field, and therefore, more investigation is required. Isothiocyanate group has been extensively used to investigate the magnetic communications due to the exciting adaptability towards the mode of coordination like an end‐to‐end ( EE ), end‐on ( EO ), and which play an important role in the controlling rate of antiferromagnetic and ferromagnetic interactions …”

Newly designed Mn (III)–W(V) bimetallic assembly built by manganese (III) Schiff–base and octacyanotungstate(V) building blocks: Structural topologies, and magnetic features

“…This nature of the χMT plot suggests a weak antiferromagnetic coupling between paramagnetic Mn (III) and W(V) centers through H–bonding. The faster decrease in a low‐temperature region denotes the presence of magnetic anisotropy zero‐field splitting (quite remarkable in Mn (III) centers), the effect of intramolecular interactions, or both, [ 70 ] but, the contribution of weak antiferromagnetic interactions cannot be ruled out.…”