title: Size-Dependent Ligand Quenching of Ferromagnetism in Co3(benzene)n+Clusters Studied with X-ray Magnetic Circular Dichroism Spectroscopy.
abstract: Cobalt-benzene cluster ions of the form Co3(bz)n+(n = 0-3) were produced in the gas phase, mass-selected, and cooled in a cryogenic ion trap held at 3-4 K. To explore ligand effects on cluster magnetic moments, these species were investigated with X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) spectroscopy. XMCD spectra yield both the spin and orbital angular momenta of these clusters. Co3+has a spin magnetic moment of μS= 6 μBand an orbital magnetic moment of μL= 3 μB. Co3(bz)+and Co3(bz)2+complexes were found to have spin and orbital magnetic moments identical to the values for ligand-free Co3+. However, coordination of the third benzene to form Co3(bz)3+completely quenches the high spin state of the system. Density functional theory calculations elucidate the spin states of the Co3(bz)n+species as a function of the number of attached benzene ligands, explaining the transition from septet to singlet for n = 0 → 3.
authors: Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States.
authors: Scott T
authors: ST
authors: Akin
authors: Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany.|Physikalisches Institut, Universität Freiburg , Stefan-Meier-Straße 21, 79104 Freiburg, Germany.
authors: Vicente
authors: V
authors: Zamudio-Bayer
authors: Department of Chemistry, Chemical Theory Center, and the Supercomputing Institute, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors: Kaining
authors: K
authors: Duanmu
authors: Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany.|Institut für Optik und Atomare Physik, Technische Universität Berlin , Hardenbergstraße 36, 10623 Berlin, Germany.
authors: Georg
authors: G
authors: Leistner
authors: Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany.|Institut für Optik und Atomare Physik, Technische Universität Berlin , Hardenbergstraße 36, 10623 Berlin, Germany.
authors: Konstantin
authors: K
authors: Hirsch
authors: Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany.|Institut für Optik und Atomare Physik, Technische Universität Berlin , Hardenbergstraße 36, 10623 Berlin, Germany.
authors: Christine
authors: C
authors: Bülow
authors: Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany.
authors: Arkadiusz
authors: A
authors: Ławicki
authors: East Tokyo Laboratory, Genesis Research Institute, Inc. , 717-86 Futamata, Ichikawa, Chiba 272-0001, Japan.|Department of Chemistry, Faculty of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
authors: Akira
authors: A
authors: Terasaki
authors: Physikalisches Institut, Universität Freiburg , Stefan-Meier-Straße 21, 79104 Freiburg, Germany.
authors: Bernd von
authors: BV
authors: Issendorff
authors: Department of Chemistry, Chemical Theory Center, and the Supercomputing Institute, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors: Donald G
authors: DG
authors: Truhlar
authors: Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany.
authors: J Tobias
authors: JT
authors: Lau
authors: Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States.
authors: Michael A
authors: MA
authors: Duncan