title: Orbital angular momentum contribution to the magneto-optical behavior of a binuclear cobalt(II) complex.
abstract: We report magnetic and magnetic circular dichroism investigations of a binuclear Co(II) compound. The Hamiltonian of the system involves an isotropic exchange interaction dealing with the real spins of cobalt(II) ions, spin-orbit coupling, and a low-symmetry crystal field acting within the (4)T(1g) ground manifold of each cobalt ion. It is shown that spin-orbit coupling between this ground term and the low-lying excited ones can be taken into consideration as an effective g factor in the Zeeman part of the Hamiltonian. The value of this g factor is estimated for the averaged experimental values of Racah and cubic ligand field parameters for high-spin cobalt(II). The treatment of the Hamiltonian is performed with the use of a irreducible tensor operator technique. The results of the calculation are in good agreement with experimental observations. Both a large effective g factor for the ground state and a large temperature-independent part of the magnetic susceptibility arise because of a strong orbital contribution to the magnetic behavior of the Co(II) dimer.
authors.affiliation: Institute of Applied Physics, Academy of Sciences of Moldova, Academy str. 5, MD-2028 Chisinau, Moldova. sm_ostrovsky@yahoo.com
authors.forename: S M
authors.initials: SM
authors.lastname: Ostrovsky
authors.forename: K
authors.initials: K
authors.lastname: Falk
authors.forename: J
authors.initials: J
authors.lastname: Pelikan
authors.forename: D A
authors.initials: DA
authors.lastname: Brown
authors.forename: Z
authors.initials: Z
authors.lastname: Tomkowicz
authors.forename: W
authors.initials: W
authors.lastname: Haase
mesh_terms: D002942:Circular Dichroism; D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D019281:Dimerization; D008280:Magnetics; D008958:Models, Molecular; D055095:Optics and Photonics; D009942:Organometallic Compounds / Q000737:chemistry*; D011789:Quantum Theory; D013696:Temperature
chemical_list: D009942:Organometallic Compounds; D003035:Cobalt