Related Experiment Video
Updated: Jun 19, 2026
Preparation of SNS Cobalt(II) Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Direct synthesis, crystal structure, high-Field EPR, and magnetic studies on an octanuclear heterometallic Cu(II)/Cd
Elena A Buvaylo1, Vladimir N Kokozay, Olga Yu Vassilyeva
1Department of Inorganic Chemistry, National Taras Shevchenko University, Volodimirska str. 64, Kyiv 01033, Ukraine.
Abstract:
The reaction of zerovalent copper with cadmium iodide and triethanolamine (H(3)L) in dimethylformamide (dmf) carried out under open-air conditions afforded a novel heterometallic complex [Cu(3)(HL)(3)CdI(2)](2) x 4 dmf. The crystal lattice consists of an octanuclear molecule [Cu(3)(HL)(3)CdI(2)](2), which has an inversion center at the midpoint of the central Cu(2)O(2) unit, and of two non-coordinating dmf molecules. Eight metal atoms linked by alkoxide arms of triethanolamine ligands form a zigzag Cd-Cu1-Cu2-Cu3-Cu4-Cu5-Cu6-Cd chain with the separations between bridged Cu atoms in the range 2.935(2)-3.403(2) A. The complex is further stabilized by intramolecular O-H...O hydrogen bonds. High-field electron paramagnetic resonance (EPR) spectra of the S = 1 spin state with D((S=1)) = -0.843 cm(-1), E((S=1)) = -0.081 cm(-1) were observed. Fitting the magnetic susceptibility temperature dependence by using the exchange Hamiltonian H(HDVV) = J(1)(S(1)S(2) + S(5)S(6)) + J(2)(S(2)S(3) + S(4)S(5) )+ J(3)S(3)S(4), to which terms expressing the zero-field splitting and Zeeman splitting of the ground S = 1 state were added, resulted in J(1) = 68, J(2) = 19, J(3) = -57 cm(-1). "Broken symmetry" DFT calculations correctly predicted the triplet ground state of the hexa-copper system.
More Related Videos
Related Concept Videos
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
03:02Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
02:42Valence Bond Theory
01:22EDTA: Chemistry and Properties
01:26EDTA: Auxiliary Complexing Reagents