title: Direct synthesis, crystal structure, high-Field EPR, and magnetic studies on an octanuclear heterometallic Cu(II)/Cd complex of triethanolamine.
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.
authors.affiliation: Department of Inorganic Chemistry, National Taras Shevchenko University, Volodimirska str. 64, Kyiv 01033, Ukraine.
authors.forename: Elena A
authors.initials: EA
authors.lastname: Buvaylo
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Kokozay
authors.forename: Olga Yu
authors.initials: OY
authors.lastname: Vassilyeva
authors.forename: Brian W
authors.initials: BW
authors.lastname: Skelton
authors.forename: Igor L
authors.initials: IL
authors.lastname: Eremenko
authors.forename: Julia
authors.initials: J
authors.lastname: Jezierska
authors.forename: Andrew
authors.initials: A
authors.lastname: Ozarowski
mesh_terms: D002104:Cadmium / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004578:Electron Spin Resonance Spectroscopy; D004983:Ethanolamines / Q000737:chemistry*; D008280:Magnetics; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D004983:Ethanolamines; D009942:Organometallic Compounds; D002104:Cadmium; D003300:Copper; C009546:triethanolamine