title: Isomorphous replacement of M(II) ions in M(II)-Gd(III) dimers (M(II) = Cu(II), Mn(II), Ni(II), Co(II), Zn(II)): magnetic studies of the products.
abstract: Complexes [M(II)Gd(III){pyCO(OEt)pyC(OH)(OEt)py}₃](ClO₄)₂·EtOH [M(II) = Cu(II) (1), Mn(II) (2), Ni(II) (3), Co(II) (4) and Zn(II) (5)] crystallize in the monoclinic Cc space group and contain one hexacoordinate M(II) ion and one enneacoordinate Gd(III) ion, bridged by three {pyCO(OEt)pyC(OH)(OEt)py}⁻ ligands. Magnetic susceptibility measurements indicate a ferromagnetic interaction for 1 and antiferromagnetic interactions for 2-4. Using the Ĥ = -JŜ(Gd(III))Ŝ(M(II)) spin Hamiltonian formalism, fits to the magnetic susceptibility data yielded J values of +0.32 cm⁻¹ for 1, -1.7 cm⁻¹ for 2, and -0.22 cm⁻¹ for 3. In complex 4, the orbital contributions of Co(II) precluded the determination of the magnetic coupling. The complex follows the Curie-Weiss law with θ = -2.07 K (-1.44 cm⁻¹).
authors.affiliation: Institute of Materials Science, NCSR Demokritos, 153 10, Aghia Paraskevi Attikis, Greece.
authors.forename: Anastasia N
authors.initials: AN
authors.lastname: Georgopoulou
authors.forename: Rosa
authors.initials: R
authors.lastname: Adam
authors.forename: Catherine P
authors.initials: CP
authors.lastname: Raptopoulou
authors.forename: Vassilis
authors.initials: V
authors.lastname: Psycharis
authors.forename: Rafael
authors.initials: R
authors.lastname: Ballesteros
authors.forename: Belén
authors.initials: B
authors.lastname: Abarca
authors.forename: Athanassios K
authors.initials: AK
authors.lastname: Boudalis
mesh_terms: D003035:Cobalt / Q000737:chemistry; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D003300:Copper / Q000737:chemistry; D018360:Crystallography, X-Ray; D019281:Dimerization; D005682:Gadolinium / Q000737:chemistry*; D008280:Magnetics; D008345:Manganese / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008968:Molecular Conformation; D009532:Nickel / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
chemical_list: D056831:Coordination Complexes; D008670:Metals; D003035:Cobalt; D008345:Manganese; D003300:Copper; D009532:Nickel; D005682:Gadolinium; D015032:Zinc